Construction of quaternary stereogenic centers via [2 + 2] cycloaddition reactions. Synthesis of homochiral 4,4-disubstituted 2-azetidinones and imine substituent effects on β-lactam formation

Journal of Organic Chemistry

Volumn 62, Issue 7, 1997, Pages 2070-2079

  Palomo, Claudio ^a   Aizpurua, Jesus M ^a   García, Jesus M ^a,b   Galarza, Regina ^a   Legido, Marta ^a   Urchegui, Raquel ^a   Román, Pascual ^a   Luque, Antonio ^a   Server Carrió, Juan ^c   Linden, Anthony ^d  

^a UNIVERSITY OF THE BASQUE COUNTRY UPV EHU   (Spain)

^b PUBLIC UNIVERSITY OF NAVARRE   (Spain)

^c UNIVERSITY OF VALENCIA   (Spain)

^d UNIVERSITY OF ZURICH   (Switzerland)

Author keywords

[No Author keywords available]

Indexed keywords

2 AZETIDINONE DERIVATIVE;

ARTICLE; DRUG SYNTHESIS; IN VITRO STUDY; NUCLEAR MAGNETIC RESONANCE; REACTION ANALYSIS; STEREOCHEMISTRY;

EID: 8244235132     PISSN: 00223263     EISSN: None     Source Type: Journal    
DOI: 10.1021/jo962017z     Document Type: Article

References (121)

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5. For some representative examples of enolate or enamine alkylations, see: (a) Ando, K.; Takema, Y.; Tomioka, K.; Koga, K. Tetrahedron 1993, 49, 1579. (b) Enders, D.; Zamponi, A.; Schëfer, T.; Nübling, C.; Eichenauer, H.; Demir, A. S.; Raabe, G. Chem. Ber. 1994, 127, 1707 and references therein. Aldol reaction: (c) Mateos, A. F.; Coca, G. P.; Perez-Alonso, J. J.; Gonzalez, R. R.; Hernandez, C. T. Tetrahedron Lett. 1995, 36, 961. (d) Kobayashi, S.; Horibe, M.; Saito, Y. Tetrahedron 1994, 50, 9629. Michael addition: (e) Barta, N. S.; Brode, A.; Stille, J. R. J. Am. Chem. Soc. 1994, 116, 6201. (f) Gautschi, M.; Schweizer, W. B.; Seebach, D. Chem. Ber. 1994, 127, 565. Diels-Alder: (f) Boeckman, R. K. Jr.; Nelson, S. G.; Gaul, M. D. J. Am. Chem. Soc. 1992, 114, 2258.
6. For some representative examples of enolate or enamine alkylations, see: (a) Ando, K.; Takema, Y.; Tomioka, K.; Koga, K. Tetrahedron 1993, 49, 1579. (b) Enders, D.; Zamponi, A.; Schëfer, T.; Nübling, C.; Eichenauer, H.; Demir, A. S.; Raabe, G. Chem. Ber. 1994, 127, 1707 and references therein. Aldol reaction: (c) Mateos, A. F.; Coca, G. P.; Perez-Alonso, J. J.; Gonzalez, R. R.; Hernandez, C. T. Tetrahedron Lett. 1995, 36, 961. (d) Kobayashi, S.; Horibe, M.; Saito, Y. Tetrahedron 1994, 50, 9629. Michael addition: (e) Barta, N. S.; Brode, A.; Stille, J. R. J. Am. Chem. Soc. 1994, 116, 6201. (f) Gautschi, M.; Schweizer, W. B.; Seebach, D. Chem. Ber. 1994, 127, 565. Diels-Alder: (f) Boeckman, R. K. Jr.; Nelson, S. G.; Gaul, M. D. J. Am. Chem. Soc. 1992, 114, 2258.
7. For some representative examples of enolate or enamine alkylations, see: (a) Ando, K.; Takema, Y.; Tomioka, K.; Koga, K. Tetrahedron 1993, 49, 1579. (b) Enders, D.; Zamponi, A.; Schëfer, T.; Nübling, C.; Eichenauer, H.; Demir, A. S.; Raabe, G. Chem. Ber. 1994, 127, 1707 and references therein. Aldol reaction: (c) Mateos, A. F.; Coca, G. P.; Perez-Alonso, J. J.; Gonzalez, R. R.; Hernandez, C. T. Tetrahedron Lett. 1995, 36, 961. (d) Kobayashi, S.; Horibe, M.; Saito, Y. Tetrahedron 1994, 50, 9629. Michael addition: (e) Barta, N. S.; Brode, A.; Stille, J. R. J. Am. Chem. Soc. 1994, 116, 6201. (f) Gautschi, M.; Schweizer, W. B.; Seebach, D. Chem. Ber. 1994, 127, 565. Diels-Alder: (f) Boeckman, R. K. Jr.; Nelson, S. G.; Gaul, M. D. J. Am. Chem. Soc. 1992, 114, 2258.
8. For some representative examples of enolate or enamine alkylations, see: (a) Ando, K.; Takema, Y.; Tomioka, K.; Koga, K. Tetrahedron 1993, 49, 1579. (b) Enders, D.; Zamponi, A.; Schëfer, T.; Nübling, C.; Eichenauer, H.; Demir, A. S.; Raabe, G. Chem. Ber. 1994, 127, 1707 and references therein. Aldol reaction: (c) Mateos, A. F.; Coca, G. P.; Perez-Alonso, J. J.; Gonzalez, R. R.; Hernandez, C. T. Tetrahedron Lett. 1995, 36, 961. (d) Kobayashi, S.; Horibe, M.; Saito, Y. Tetrahedron 1994, 50, 9629. Michael addition: (e) Barta, N. S.; Brode, A.; Stille, J. R. J. Am. Chem. Soc. 1994, 116, 6201. (f) Gautschi, M.; Schweizer, W. B.; Seebach, D. Chem. Ber. 1994, 127, 565. Diels-Alder: (f) Boeckman, R. K. Jr.; Nelson, S. G.; Gaul, M. D. J. Am. Chem. Soc. 1992, 114, 2258.
9. For some representative examples of enolate or enamine alkylations, see: (a) Ando, K.; Takema, Y.; Tomioka, K.; Koga, K. Tetrahedron 1993, 49, 1579. (b) Enders, D.; Zamponi, A.; Schëfer, T.; Nübling, C.; Eichenauer, H.; Demir, A. S.; Raabe, G. Chem. Ber. 1994, 127, 1707 and references therein. Aldol reaction: (c) Mateos, A. F.; Coca, G. P.; Perez-Alonso, J. J.; Gonzalez, R. R.; Hernandez, C. T. Tetrahedron Lett. 1995, 36, 961. (d) Kobayashi, S.; Horibe, M.; Saito, Y. Tetrahedron 1994, 50, 9629. Michael addition: (e) Barta, N. S.; Brode, A.; Stille, J. R. J. Am. Chem. Soc. 1994, 116, 6201. (f) Gautschi, M.; Schweizer, W. B.; Seebach, D. Chem. Ber. 1994, 127, 565. Diels-Alder: (f) Boeckman, R. K. Jr.; Nelson, S. G.; Gaul, M. D. J. Am. Chem. Soc. 1992, 114, 2258.
10. For some representative examples of enolate or enamine alkylations, see: (a) Ando, K.; Takema, Y.; Tomioka, K.; Koga, K. Tetrahedron 1993, 49, 1579. (b) Enders, D.; Zamponi, A.; Schëfer, T.; Nübling, C.; Eichenauer, H.; Demir, A. S.; Raabe, G. Chem. Ber. 1994, 127, 1707 and references therein. Aldol reaction: (c) Mateos, A. F.; Coca, G. P.; Perez-Alonso, J. J.; Gonzalez, R. R.; Hernandez, C. T. Tetrahedron Lett. 1995, 36, 961. (d) Kobayashi, S.; Horibe, M.; Saito, Y. Tetrahedron 1994, 50, 9629. Michael addition: (e) Barta, N. S.; Brode, A.; Stille, J. R. J. Am. Chem. Soc. 1994, 116, 6201. (f) Gautschi, M.; Schweizer, W. B.; Seebach, D. Chem. Ber. 1994, 127, 565. Diels-Alder: (f) Boeckman, R. K. Jr.; Nelson, S. G.; Gaul, M. D. J. Am. Chem. Soc. 1992, 114, 2258.
11. Butenolides: (a) Miller, M. Hegedus, L. S. J. Org. Chem. 1993, 58, 6779. Cyclobutanes: (b) Narasaka, N.; Hayashi, Y.; Shimadzu, H.; Niihata, S. J. Am. Chem. Soc. 1992, 114, 8869.
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15. Reviews on β-lactam antibiotics: (a) Morin, R. B.; Gorman, M. Chemistry and Biology of β-Lactam Antibiotics; Academic Press: New York, 1982; Vols. 1-3. (b) Bentley, P. M.; Southgate, R. Recent Advances in the Chemistry of β-Lactam Antibiotics; The Royal Society of Chemistry: London, 1988. Durckheimer, W.; Blumbach, J.; Lattrell, R.; Sheunemann, K. H. Angew. Chem., Int. Ed. Engl. 1985, 24, 180. Southgate, R. Contemp. Org. Synth. 1994, 1, 417.
16. Reviews on β-lactam antibiotics: (a) Morin, R. B.; Gorman, M. Chemistry and Biology of β-Lactam Antibiotics; Academic Press: New York, 1982; Vols. 1-3. (b) Bentley, P. M.; Southgate, R. Recent Advances in the Chemistry of β-Lactam Antibiotics; The Royal Society of Chemistry: London, 1988. Durckheimer, W.; Blumbach, J.; Lattrell, R.; Sheunemann, K. H. Angew. Chem., Int. Ed. Engl. 1985, 24, 180. Southgate, R. Contemp. Org. Synth. 1994, 1, 417.
17. Reviews on β-lactam antibiotics: (a) Morin, R. B.; Gorman, M. Chemistry and Biology of β-Lactam Antibiotics; Academic Press: New York, 1982; Vols. 1-3. (b) Bentley, P. M.; Southgate, R. Recent Advances in the Chemistry of β-Lactam Antibiotics; The Royal Society of Chemistry: London, 1988. Durckheimer, W.; Blumbach, J.; Lattrell, R.; Sheunemann, K. H. Angew. Chem., Int. Ed. Engl. 1985, 24, 180. Southgate, R. Contemp. Org. Synth. 1994, 1, 417.
18. Reviews on β-lactam antibiotics: (a) Morin, R. B.; Gorman, M. Chemistry and Biology of β-Lactam Antibiotics; Academic Press: New York, 1982; Vols. 1-3. (b) Bentley, P. M.; Southgate, R. Recent Advances in the Chemistry of β-Lactam Antibiotics; The Royal Society of Chemistry: London, 1988. Durckheimer, W.; Blumbach, J.; Lattrell, R.; Sheunemann, K. H. Angew. Chem., Int. Ed. Engl. 1985, 24, 180. Southgate, R. Contemp. Org. Synth. 1994, 1, 417.
19. (a) Pratt, R. F. In Design of Enzyme Inhibitors as Drugs; Sandler, M., Smith, H. J., Eds., Oxford University Press; New York, 1989; p 178.
20. (b) The Chemistry of β-Lactams; Page, M. I., Ed., Chapman and Hall: London, 1992
21. . (9) (a) Gordon, E. M.; Ondetti, M. A.; Pluscec, J.; Cimarusti, C. M.; Bonner, D. P.; Sykes, R. B. J. Am. Chem. Soc. 1982, 104, 6053.
22. (b) Koster, W. H.; Bonner, D. P. In Frontiers of Antibiotic Research; Umezawa, H., Ed.; Academic Press: New York, 1987; p 211.
23. For representative examples, see: (a) Palomo, C.; Aizpurua, J. M. Trends Org. Chem. 1993, 4, 637. α-Amino acid N-carboxy anhydrides: (b) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Carreaux, F.; Cuevas, C.; Maneiro, E.; Ontoria, J. M. J. Org. Chem. 1994, 59, 3123. (c) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Maneiro, E.; Odriozola, B. J. Chem. Soc., Chem. Commun. 1994, 1505. α-Hydroxy β-amino acid-derived peptides: (d) Palomo, C.; Aizpurua, J. M.; Cabré, P.; García, J. M.; Odriozola, J. M. Tetrahedron Lett. 1994, 35, 2721. (e) Palomo, C.; Aizpurua, J. M.; Cuevas, C. J. Chem. Soc., Chem. Commun. 1994, 1957. 1,3-Polyols and 2-amino-1,3-polyols: (f) Palomo, C.; Aizpurua, J. M.; Urchegui, R.; García, J. M. J. Org. Chem. 1993, 58, 1646. β-Amino ketones: (g) Palomo, C.; Aizpurua, J. M.; García, J. M.; Iturburu, M.; Odriozola, J. M. J. Org. Chem. 1994, 59, 5184. α-Amino acid peptide fragments of lysobactin: (h) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Odriozola, B.; Maneiro, E.; Miranda, J. I.; Urchegui, R. J. Chem. Soc., Chem. Commun. 1996, 161. α-Branched β-alkylserine peptides: Palomo, C.; Aizpurua, J. M.; Urchegui, R.; Garcia, J. M. J. Chem. Soc., Chem. Commun. 1995, 2327. β-Substituted aspartic acids: (j) Palomo, C.; Cabré, F.; Ontoria, J. M. Tetrahedron Lett. 1992, 33, 4819. (k) Palomo, C.; Aizpurua, J. M.; Ontoria, J. M.; Iturburu, M. Tetrahedron Lett. 1992, 33, 4823. Palomo, C.; Aizpurua, J. M.; Ganboa, I. In Enantioselective Synthesis of β-Amino Acids; Juaristi, E., Ed.; VCH: New York, 1997, in press.
24. For representative examples, see: (a) Palomo, C.; Aizpurua, J. M. Trends Org. Chem. 1993, 4, 637. α-Amino acid N-carboxy anhydrides: (b) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Carreaux, F.; Cuevas, C.; Maneiro, E.; Ontoria, J. M. J. Org. Chem. 1994, 59, 3123. (c) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Maneiro, E.; Odriozola, B. J. Chem. Soc., Chem. Commun. 1994, 1505. α-Hydroxy β-amino acid-derived peptides: (d) Palomo, C.; Aizpurua, J. M.; Cabré, P.; García, J. M.; Odriozola, J. M. Tetrahedron Lett. 1994, 35, 2721. (e) Palomo, C.; Aizpurua, J. M.; Cuevas, C. J. Chem. Soc., Chem. Commun. 1994, 1957. 1,3-Polyols and 2-amino-1,3-polyols: (f) Palomo, C.; Aizpurua, J. M.; Urchegui, R.; García, J. M. J. Org. Chem. 1993, 58, 1646. β-Amino ketones: (g) Palomo, C.; Aizpurua, J. M.; García, J. M.; Iturburu, M.; Odriozola, J. M. J. Org. Chem. 1994, 59, 5184. α-Amino acid peptide fragments of lysobactin: (h) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Odriozola, B.; Maneiro, E.; Miranda, J. I.; Urchegui, R. J. Chem. Soc., Chem. Commun. 1996, 161. α-Branched β-alkylserine peptides: Palomo, C.; Aizpurua, J. M.; Urchegui, R.; Garcia, J. M. J. Chem. Soc., Chem. Commun. 1995, 2327. β-Substituted aspartic acids: (j) Palomo, C.; Cabré, F.; Ontoria, J. M. Tetrahedron Lett. 1992, 33, 4819. (k) Palomo, C.; Aizpurua, J. M.; Ontoria, J. M.; Iturburu, M. Tetrahedron Lett. 1992, 33, 4823. Palomo, C.; Aizpurua, J. M.; Ganboa, I. In Enantioselective Synthesis of β-Amino Acids; Juaristi, E., Ed.; VCH: New York, 1997, in press.
25. For representative examples, see: (a) Palomo, C.; Aizpurua, J. M. Trends Org. Chem. 1993, 4, 637. α-Amino acid N-carboxy anhydrides: (b) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Carreaux, F.; Cuevas, C.; Maneiro, E.; Ontoria, J. M. J. Org. Chem. 1994, 59, 3123. (c) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Maneiro, E.; Odriozola, B. J. Chem. Soc., Chem. Commun. 1994, 1505. α-Hydroxy β-amino acid-derived peptides: (d) Palomo, C.; Aizpurua, J. M.; Cabré, P.; García, J. M.; Odriozola, J. M. Tetrahedron Lett. 1994, 35, 2721. (e) Palomo, C.; Aizpurua, J. M.; Cuevas, C. J. Chem. Soc., Chem. Commun. 1994, 1957. 1,3-Polyols and 2-amino-1,3-polyols: (f) Palomo, C.; Aizpurua, J. M.; Urchegui, R.; García, J. M. J. Org. Chem. 1993, 58, 1646. β-Amino ketones: (g) Palomo, C.; Aizpurua, J. M.; García, J. M.; Iturburu, M.; Odriozola, J. M. J. Org. Chem. 1994, 59, 5184. α-Amino acid peptide fragments of lysobactin: (h) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Odriozola, B.; Maneiro, E.; Miranda, J. I.; Urchegui, R. J. Chem. Soc., Chem. Commun. 1996, 161. α-Branched β-alkylserine peptides: Palomo, C.; Aizpurua, J. M.; Urchegui, R.; Garcia, J. M. J. Chem. Soc., Chem. Commun. 1995, 2327. β-Substituted aspartic acids: (j) Palomo, C.; Cabré, F.; Ontoria, J. M. Tetrahedron Lett. 1992, 33, 4819. (k) Palomo, C.; Aizpurua, J. M.; Ontoria, J. M.; Iturburu, M. Tetrahedron Lett. 1992, 33, 4823. Palomo, C.; Aizpurua, J. M.; Ganboa, I. In Enantioselective Synthesis of β-Amino Acids; Juaristi, E., Ed.; VCH: New York, 1997, in press.
26. For representative examples, see: (a) Palomo, C.; Aizpurua, J. M. Trends Org. Chem. 1993, 4, 637. α-Amino acid N-carboxy anhydrides: (b) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Carreaux, F.; Cuevas, C.; Maneiro, E.; Ontoria, J. M. J. Org. Chem. 1994, 59, 3123. (c) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Maneiro, E.; Odriozola, B. J. Chem. Soc., Chem. Commun. 1994, 1505. α-Hydroxy β-amino acid-derived peptides: (d) Palomo, C.; Aizpurua, J. M.; Cabré, P.; García, J. M.; Odriozola, J. M. Tetrahedron Lett. 1994, 35, 2721. (e) Palomo, C.; Aizpurua, J. M.; Cuevas, C. J. Chem. Soc., Chem. Commun. 1994, 1957. 1,3-Polyols and 2-amino-1,3-polyols: (f) Palomo, C.; Aizpurua, J. M.; Urchegui, R.; García, J. M. J. Org. Chem. 1993, 58, 1646. β-Amino ketones: (g) Palomo, C.; Aizpurua, J. M.; García, J. M.; Iturburu, M.; Odriozola, J. M. J. Org. Chem. 1994, 59, 5184. α-Amino acid peptide fragments of lysobactin: (h) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Odriozola, B.; Maneiro, E.; Miranda, J. I.; Urchegui, R. J. Chem. Soc., Chem. Commun. 1996, 161. α-Branched β-alkylserine peptides: Palomo, C.; Aizpurua, J. M.; Urchegui, R.; Garcia, J. M. J. Chem. Soc., Chem. Commun. 1995, 2327. β-Substituted aspartic acids: (j) Palomo, C.; Cabré, F.; Ontoria, J. M. Tetrahedron Lett. 1992, 33, 4819. (k) Palomo, C.; Aizpurua, J. M.; Ontoria, J. M.; Iturburu, M. Tetrahedron Lett. 1992, 33, 4823. Palomo, C.; Aizpurua, J. M.; Ganboa, I. In Enantioselective Synthesis of β-Amino Acids; Juaristi, E., Ed.; VCH: New York, 1997, in press.
27. For representative examples, see: (a) Palomo, C.; Aizpurua, J. M. Trends Org. Chem. 1993, 4, 637. α-Amino acid N-carboxy anhydrides: (b) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Carreaux, F.; Cuevas, C.; Maneiro, E.; Ontoria, J. M. J. Org. Chem. 1994, 59, 3123. (c) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Maneiro, E.; Odriozola, B. J. Chem. Soc., Chem. Commun. 1994, 1505. α-Hydroxy β-amino acid-derived peptides: (d) Palomo, C.; Aizpurua, J. M.; Cabré, P.; García, J. M.; Odriozola, J. M. Tetrahedron Lett. 1994, 35, 2721. (e) Palomo, C.; Aizpurua, J. M.; Cuevas, C. J. Chem. Soc., Chem. Commun. 1994, 1957. 1,3-Polyols and 2-amino-1,3-polyols: (f) Palomo, C.; Aizpurua, J. M.; Urchegui, R.; García, J. M. J. Org. Chem. 1993, 58, 1646. β-Amino ketones: (g) Palomo, C.; Aizpurua, J. M.; García, J. M.; Iturburu, M.; Odriozola, J. M. J. Org. Chem. 1994, 59, 5184. α-Amino acid peptide fragments of lysobactin: (h) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Odriozola, B.; Maneiro, E.; Miranda, J. I.; Urchegui, R. J. Chem. Soc., Chem. Commun. 1996, 161. α-Branched β-alkylserine peptides: Palomo, C.; Aizpurua, J. M.; Urchegui, R.; Garcia, J. M. J. Chem. Soc., Chem. Commun. 1995, 2327. β-Substituted aspartic acids: (j) Palomo, C.; Cabré, F.; Ontoria, J. M. Tetrahedron Lett. 1992, 33, 4819. (k) Palomo, C.; Aizpurua, J. M.; Ontoria, J. M.; Iturburu, M. Tetrahedron Lett. 1992, 33, 4823. Palomo, C.; Aizpurua, J. M.; Ganboa, I. In Enantioselective Synthesis of β-Amino Acids; Juaristi, E., Ed.; VCH: New York, 1997, in press.
28. For representative examples, see: (a) Palomo, C.; Aizpurua, J. M. Trends Org. Chem. 1993, 4, 637. α-Amino acid N-carboxy anhydrides: (b) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Carreaux, F.; Cuevas, C.; Maneiro, E.; Ontoria, J. M. J. Org. Chem. 1994, 59, 3123. (c) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Maneiro, E.; Odriozola, B. J. Chem. Soc., Chem. Commun. 1994, 1505. α-Hydroxy β-amino acid-derived peptides: (d) Palomo, C.; Aizpurua, J. M.; Cabré, P.; García, J. M.; Odriozola, J. M. Tetrahedron Lett. 1994, 35, 2721. (e) Palomo, C.; Aizpurua, J. M.; Cuevas, C. J. Chem. Soc., Chem. Commun. 1994, 1957. 1,3-Polyols and 2-amino-1,3-polyols: (f) Palomo, C.; Aizpurua, J. M.; Urchegui, R.; García, J. M. J. Org. Chem. 1993, 58, 1646. β-Amino ketones: (g) Palomo, C.; Aizpurua, J. M.; García, J. M.; Iturburu, M.; Odriozola, J. M. J. Org. Chem. 1994, 59, 5184. α-Amino acid peptide fragments of lysobactin: (h) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Odriozola, B.; Maneiro, E.; Miranda, J. I.; Urchegui, R. J. Chem. Soc., Chem. Commun. 1996, 161. α-Branched β-alkylserine peptides: Palomo, C.; Aizpurua, J. M.; Urchegui, R.; Garcia, J. M. J. Chem. Soc., Chem. Commun. 1995, 2327. β-Substituted aspartic acids: (j) Palomo, C.; Cabré, F.; Ontoria, J. M. Tetrahedron Lett. 1992, 33, 4819. (k) Palomo, C.; Aizpurua, J. M.; Ontoria, J. M.; Iturburu, M. Tetrahedron Lett. 1992, 33, 4823. Palomo, C.; Aizpurua, J. M.; Ganboa, I. In Enantioselective Synthesis of β-Amino Acids; Juaristi, E., Ed.; VCH: New York, 1997, in press.
29. For representative examples, see: (a) Palomo, C.; Aizpurua, J. M. Trends Org. Chem. 1993, 4, 637. α-Amino acid N-carboxy anhydrides: (b) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Carreaux, F.; Cuevas, C.; Maneiro, E.; Ontoria, J. M. J. Org. Chem. 1994, 59, 3123. (c) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Maneiro, E.; Odriozola, B. J. Chem. Soc., Chem. Commun. 1994, 1505. α-Hydroxy β-amino acid-derived peptides: (d) Palomo, C.; Aizpurua, J. M.; Cabré, P.; García, J. M.; Odriozola, J. M. Tetrahedron Lett. 1994, 35, 2721. (e) Palomo, C.; Aizpurua, J. M.; Cuevas, C. J. Chem. Soc., Chem. Commun. 1994, 1957. 1,3-Polyols and 2-amino-1,3-polyols: (f) Palomo, C.; Aizpurua, J. M.; Urchegui, R.; García, J. M. J. Org. Chem. 1993, 58, 1646. β-Amino ketones: (g) Palomo, C.; Aizpurua, J. M.; García, J. M.; Iturburu, M.; Odriozola, J. M. J. Org. Chem. 1994, 59, 5184. α-Amino acid peptide fragments of lysobactin: (h) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Odriozola, B.; Maneiro, E.; Miranda, J. I.; Urchegui, R. J. Chem. Soc., Chem. Commun. 1996, 161. α-Branched β-alkylserine peptides: Palomo, C.; Aizpurua, J. M.; Urchegui, R.; Garcia, J. M. J. Chem. Soc., Chem. Commun. 1995, 2327. β-Substituted aspartic acids: (j) Palomo, C.; Cabré, F.; Ontoria, J. M. Tetrahedron Lett. 1992, 33, 4819. (k) Palomo, C.; Aizpurua, J. M.; Ontoria, J. M.; Iturburu, M. Tetrahedron Lett. 1992, 33, 4823. Palomo, C.; Aizpurua, J. M.; Ganboa, I. In Enantioselective Synthesis of β-Amino Acids; Juaristi, E., Ed.; VCH: New York, 1997, in press.
30. For representative examples, see: (a) Palomo, C.; Aizpurua, J. M. Trends Org. Chem. 1993, 4, 637. α-Amino acid N-carboxy anhydrides: (b) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Carreaux, F.; Cuevas, C.; Maneiro, E.; Ontoria, J. M. J. Org. Chem. 1994, 59, 3123. (c) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Maneiro, E.; Odriozola, B. J. Chem. Soc., Chem. Commun. 1994, 1505. α-Hydroxy β-amino acid-derived peptides: (d) Palomo, C.; Aizpurua, J. M.; Cabré, P.; García, J. M.; Odriozola, J. M. Tetrahedron Lett. 1994, 35, 2721. (e) Palomo, C.; Aizpurua, J. M.; Cuevas, C. J. Chem. Soc., Chem. Commun. 1994, 1957. 1,3-Polyols and 2-amino-1,3-polyols: (f) Palomo, C.; Aizpurua, J. M.; Urchegui, R.; García, J. M. J. Org. Chem. 1993, 58, 1646. β-Amino ketones: (g) Palomo, C.; Aizpurua, J. M.; García, J. M.; Iturburu, M.; Odriozola, J. M. J. Org. Chem. 1994, 59, 5184. α-Amino acid peptide fragments of lysobactin: (h) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Odriozola, B.; Maneiro, E.; Miranda, J. I.; Urchegui, R. J. Chem. Soc., Chem. Commun. 1996, 161. α-Branched β-alkylserine peptides: Palomo, C.; Aizpurua, J. M.; Urchegui, R.; Garcia, J. M. J. Chem. Soc., Chem. Commun. 1995, 2327. β-Substituted aspartic acids: (j) Palomo, C.; Cabré, F.; Ontoria, J. M. Tetrahedron Lett. 1992, 33, 4819. (k) Palomo, C.; Aizpurua, J. M.; Ontoria, J. M.; Iturburu, M. Tetrahedron Lett. 1992, 33, 4823. Palomo, C.; Aizpurua, J. M.; Ganboa, I. In Enantioselective Synthesis of β-Amino Acids; Juaristi, E., Ed.; VCH: New York, 1997, in press.
31. For representative examples, see: (a) Palomo, C.; Aizpurua, J. M. Trends Org. Chem. 1993, 4, 637. α-Amino acid N-carboxy anhydrides: (b) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Carreaux, F.; Cuevas, C.; Maneiro, E.; Ontoria, J. M. J. Org. Chem. 1994, 59, 3123. (c) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Maneiro, E.; Odriozola, B. J. Chem. Soc., Chem. Commun. 1994, 1505. α-Hydroxy β-amino acid-derived peptides: (d) Palomo, C.; Aizpurua, J. M.; Cabré, P.; García, J. M.; Odriozola, J. M. Tetrahedron Lett. 1994, 35, 2721. (e) Palomo, C.; Aizpurua, J. M.; Cuevas, C. J. Chem. Soc., Chem. Commun. 1994, 1957. 1,3-Polyols and 2-amino-1,3-polyols: (f) Palomo, C.; Aizpurua, J. M.; Urchegui, R.; García, J. M. J. Org. Chem. 1993, 58, 1646. β-Amino ketones: (g) Palomo, C.; Aizpurua, J. M.; García, J. M.; Iturburu, M.; Odriozola, J. M. J. Org. Chem. 1994, 59, 5184. α-Amino acid peptide fragments of lysobactin: (h) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Odriozola, B.; Maneiro, E.; Miranda, J. I.; Urchegui, R. J. Chem. Soc., Chem. Commun. 1996, 161. α-Branched β-alkylserine peptides: Palomo, C.; Aizpurua, J. M.; Urchegui, R.; Garcia, J. M. J. Chem. Soc., Chem. Commun. 1995, 2327. β-Substituted aspartic acids: (j) Palomo, C.; Cabré, F.; Ontoria, J. M. Tetrahedron Lett. 1992, 33, 4819. (k) Palomo, C.; Aizpurua, J. M.; Ontoria, J. M.; Iturburu, M. Tetrahedron Lett. 1992, 33, 4823. Palomo, C.; Aizpurua, J. M.; Ganboa, I. In Enantioselective Synthesis of β-Amino Acids; Juaristi, E., Ed.; VCH: New York, 1997, in press.
32. For representative examples, see: (a) Palomo, C.; Aizpurua, J. M. Trends Org. Chem. 1993, 4, 637. α-Amino acid N-carboxy anhydrides: (b) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Carreaux, F.; Cuevas, C.; Maneiro, E.; Ontoria, J. M. J. Org. Chem. 1994, 59, 3123. (c) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Maneiro, E.; Odriozola, B. J. Chem. Soc., Chem. Commun. 1994, 1505. α-Hydroxy β-amino acid-derived peptides: (d) Palomo, C.; Aizpurua, J. M.; Cabré, P.; García, J. M.; Odriozola, J. M. Tetrahedron Lett. 1994, 35, 2721. (e) Palomo, C.; Aizpurua, J. M.; Cuevas, C. J. Chem. Soc., Chem. Commun. 1994, 1957. 1,3-Polyols and 2-amino-1,3-polyols: (f) Palomo, C.; Aizpurua, J. M.; Urchegui, R.; García, J. M. J. Org. Chem. 1993, 58, 1646. β-Amino ketones: (g) Palomo, C.; Aizpurua, J. M.; García, J. M.; Iturburu, M.; Odriozola, J. M. J. Org. Chem. 1994, 59, 5184. α-Amino acid peptide fragments of lysobactin: (h) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Odriozola, B.; Maneiro, E.; Miranda, J. I.; Urchegui, R. J. Chem. Soc., Chem. Commun. 1996, 161. α-Branched β-alkylserine peptides: Palomo, C.; Aizpurua, J. M.; Urchegui, R.; Garcia, J. M. J. Chem. Soc., Chem. Commun. 1995, 2327. β-Substituted aspartic acids: (j) Palomo, C.; Cabré, F.; Ontoria, J. M. Tetrahedron Lett. 1992, 33, 4819. (k) Palomo, C.; Aizpurua, J. M.; Ontoria, J. M.; Iturburu, M. Tetrahedron Lett. 1992, 33, 4823. Palomo, C.; Aizpurua, J. M.; Ganboa, I. In Enantioselective Synthesis of β-Amino Acids; Juaristi, E., Ed.; VCH: New York, 1997, in press.
33. For representative examples, see: (a) Palomo, C.; Aizpurua, J. M. Trends Org. Chem. 1993, 4, 637. α-Amino acid N-carboxy anhydrides: (b) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Carreaux, F.; Cuevas, C.; Maneiro, E.; Ontoria, J. M. J. Org. Chem. 1994, 59, 3123. (c) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Maneiro, E.; Odriozola, B. J. Chem. Soc., Chem. Commun. 1994, 1505. α-Hydroxy β-amino acid-derived peptides: (d) Palomo, C.; Aizpurua, J. M.; Cabré, P.; García, J. M.; Odriozola, J. M. Tetrahedron Lett. 1994, 35, 2721. (e) Palomo, C.; Aizpurua, J. M.; Cuevas, C. J. Chem. Soc., Chem. Commun. 1994, 1957. 1,3-Polyols and 2-amino-1,3-polyols: (f) Palomo, C.; Aizpurua, J. M.; Urchegui, R.; García, J. M. J. Org. Chem. 1993, 58, 1646. β-Amino ketones: (g) Palomo, C.; Aizpurua, J. M.; García, J. M.; Iturburu, M.; Odriozola, J. M. J. Org. Chem. 1994, 59, 5184. α-Amino acid peptide fragments of lysobactin: (h) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Odriozola, B.; Maneiro, E.; Miranda, J. I.; Urchegui, R. J. Chem. Soc., Chem. Commun. 1996, 161. α-Branched β-alkylserine peptides: Palomo, C.; Aizpurua, J. M.; Urchegui, R.; Garcia, J. M. J. Chem. Soc., Chem. Commun. 1995, 2327. β-Substituted aspartic acids: (j) Palomo, C.; Cabré, F.; Ontoria, J. M. Tetrahedron Lett. 1992, 33, 4819. (k) Palomo, C.; Aizpurua, J. M.; Ontoria, J. M.; Iturburu, M. Tetrahedron Lett. 1992, 33, 4823. Palomo, C.; Aizpurua, J. M.; Ganboa, I. In Enantioselective Synthesis of β-Amino Acids; Juaristi, E., Ed.; VCH: New York, 1997, in press.
34. For representative examples, see: (a) Palomo, C.; Aizpurua, J. M. Trends Org. Chem. 1993, 4, 637. α-Amino acid N-carboxy anhydrides: (b) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Carreaux, F.; Cuevas, C.; Maneiro, E.; Ontoria, J. M. J. Org. Chem. 1994, 59, 3123. (c) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Maneiro, E.; Odriozola, B. J. Chem. Soc., Chem. Commun. 1994, 1505. α-Hydroxy β-amino acid-derived peptides: (d) Palomo, C.; Aizpurua, J. M.; Cabré, P.; García, J. M.; Odriozola, J. M. Tetrahedron Lett. 1994, 35, 2721. (e) Palomo, C.; Aizpurua, J. M.; Cuevas, C. J. Chem. Soc., Chem. Commun. 1994, 1957. 1,3-Polyols and 2-amino-1,3-polyols: (f) Palomo, C.; Aizpurua, J. M.; Urchegui, R.; García, J. M. J. Org. Chem. 1993, 58, 1646. β-Amino ketones: (g) Palomo, C.; Aizpurua, J. M.; García, J. M.; Iturburu, M.; Odriozola, J. M. J. Org. Chem. 1994, 59, 5184. α-Amino acid peptide fragments of lysobactin: (h) Palomo, C.; Aizpurua, J. M.; Ganboa, I.; Odriozola, B.; Maneiro, E.; Miranda, J. I.; Urchegui, R. J. Chem. Soc., Chem. Commun. 1996, 161. α-Branched β-alkylserine peptides: Palomo, C.; Aizpurua, J. M.; Urchegui, R.; Garcia, J. M. J. Chem. Soc., Chem. Commun. 1995, 2327. β-Substituted aspartic acids: (j) Palomo, C.; Cabré, F.; Ontoria, J. M. Tetrahedron Lett. 1992, 33, 4819. (k) Palomo, C.; Aizpurua, J. M.; Ontoria, J. M.; Iturburu, M. Tetrahedron Lett. 1992, 33, 4823. Palomo, C.; Aizpurua, J. M.; Ganboa, I. In Enantioselective Synthesis of β-Amino Acids; Juaristi, E., Ed.; VCH: New York, 1997, in press.
35. For reviews of non-β-lactam products from azetidinone frameworks, see: (a) Manhas, M. S.; Wagle, D. R.; Chiang, J.; Bose, A. K. Heterocycles 1988, 27, 1755. (b) Hesse, M. In Ring Enlargement in Organic Synthesis; VCH: Weinheim, 1991; p 97. Amino acids and peptides: (c) Ojima, I. In The Organic Chemistry of β-Lactams; Georg, G. I., Ed., VCH: New York, 1992; p 197. (d) Ojima, I. Acc. Chem. Res. 1995, 28, 383. (e) Hegedus, L. S. Acc. Chem. Res. 1995, 28, 299. Aspartic acids: (f) Hanessian, S.; Sumi, K.; Vanasse, B. Synlett 1992, 23. α,β-Diamino acids: (g) Ojima, I.; Pei, Y. Tetrahedron Lett. 1990, 31, 977. Polyhydroxyamino acids: (h) Banick, B. K.; Manhas, M. S.; Bose, A. K. J. Org. Chem. 1993, 58, 307. γ-Keto α-amino acids: Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Smith, M. L.; Russel, A. T. Synlett 1993, 51. (j) Baldwin, J. E.; Adlington, R. M.; Rusell, A. T.; Smith, M. L. Tetrahedron Lett. 1995, 57, 4733. Prolines: (k) Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Vaughan, J. G. J. Chem. Soc., Chem. Commun. 1993, 1434. Baldwin, J. E.; Rudolph, M. Tetrahedron Lett. 1994, 35, 6163. Aminosugars: (m) Ha, D.-C.; Hart, D. J. Tetrahedron Lett. 1987, 28, 4489. (n) Shiozaki, M.; Ishida, N.; Sato, S. Bull. Chem. Soc. Jpn. 1989, 62, 3950. (o) Galluci, J. C.; Ha, D.-C.; Hart, D. J. Tetrahedron 1989, 45, 1283. (p) Hauser, F. M.; Ellenberger, S. R.; Rhee, R. P. J. Org. Chem. 1987, 52, 5041. (q) Araki, K.; O'Toole, J. C.; Welch, J. T. Bioorg. Med. Chem. Lett. 1993, 3, 2457. (r) Bose, A. K.; Mathur, C.; Wagle, D. R.; Naqvi, R.; Manhas, M. S. Heterocycles 1994, 39, 491. Pyrrolizidines: (s) Cavanga, F.; Linkies, H.; Pietsch, H.; Reuschling, D. Angew. Chem., Int. Ed. Engl. 1980, 129. Pyrrolidines: (t) Bose, A. K.; Krishnan, L.; Wagle, D. R.; Manhas, M. S. Tetrahedron Lett. 1986, 27, 3955. Morfolines: (u) Wagle, D. R.; Monteleone, M. G.; Krishnan, L.; Manhas, M. S.; Bose, A. K. J. Chem. Soc., Chem. Commun. 1989, 8915.
36. For reviews of non-β-lactam products from azetidinone frameworks, see: (a) Manhas, M. S.; Wagle, D. R.; Chiang, J.; Bose, A. K. Heterocycles 1988, 27, 1755. (b) Hesse, M. In Ring Enlargement in Organic Synthesis; VCH: Weinheim, 1991; p 97. Amino acids and peptides: (c) Ojima, I. In The Organic Chemistry of β-Lactams; Georg, G. I., Ed., VCH: New York, 1992; p 197. (d) Ojima, I. Acc. Chem. Res. 1995, 28, 383. (e) Hegedus, L. S. Acc. Chem. Res. 1995, 28, 299. Aspartic acids: (f) Hanessian, S.; Sumi, K.; Vanasse, B. Synlett 1992, 23. α,β-Diamino acids: (g) Ojima, I.; Pei, Y. Tetrahedron Lett. 1990, 31, 977. Polyhydroxyamino acids: (h) Banick, B. K.; Manhas, M. S.; Bose, A. K. J. Org. Chem. 1993, 58, 307. γ-Keto α-amino acids: Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Smith, M. L.; Russel, A. T. Synlett 1993, 51. (j) Baldwin, J. E.; Adlington, R. M.; Rusell, A. T.; Smith, M. L. Tetrahedron Lett. 1995, 57, 4733. Prolines: (k) Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Vaughan, J. G. J. Chem. Soc., Chem. Commun. 1993, 1434. Baldwin, J. E.; Rudolph, M. Tetrahedron Lett. 1994, 35, 6163. Aminosugars: (m) Ha, D.-C.; Hart, D. J. Tetrahedron Lett. 1987, 28, 4489. (n) Shiozaki, M.; Ishida, N.; Sato, S. Bull. Chem. Soc. Jpn. 1989, 62, 3950. (o) Galluci, J. C.; Ha, D.-C.; Hart, D. J. Tetrahedron 1989, 45, 1283. (p) Hauser, F. M.; Ellenberger, S. R.; Rhee, R. P. J. Org. Chem. 1987, 52, 5041. (q) Araki, K.; O'Toole, J. C.; Welch, J. T. Bioorg. Med. Chem. Lett. 1993, 3, 2457. (r) Bose, A. K.; Mathur, C.; Wagle, D. R.; Naqvi, R.; Manhas, M. S. Heterocycles 1994, 39, 491. Pyrrolizidines: (s) Cavanga, F.; Linkies, H.; Pietsch, H.; Reuschling, D. Angew. Chem., Int. Ed. Engl. 1980, 129. Pyrrolidines: (t) Bose, A. K.; Krishnan, L.; Wagle, D. R.; Manhas, M. S. Tetrahedron Lett. 1986, 27, 3955. Morfolines: (u) Wagle, D. R.; Monteleone, M. G.; Krishnan, L.; Manhas, M. S.; Bose, A. K. J. Chem. Soc., Chem. Commun. 1989, 8915.
37. For reviews of non-β-lactam products from azetidinone frameworks, see: (a) Manhas, M. S.; Wagle, D. R.; Chiang, J.; Bose, A. K. Heterocycles 1988, 27, 1755. (b) Hesse, M. In Ring Enlargement in Organic Synthesis; VCH: Weinheim, 1991; p 97. Amino acids and peptides: (c) Ojima, I. In The Organic Chemistry of β-Lactams; Georg, G. I., Ed., VCH: New York, 1992; p 197. (d) Ojima, I. Acc. Chem. Res. 1995, 28, 383. (e) Hegedus, L. S. Acc. Chem. Res. 1995, 28, 299. Aspartic acids: (f) Hanessian, S.; Sumi, K.; Vanasse, B. Synlett 1992, 23. α,β-Diamino acids: (g) Ojima, I.; Pei, Y. Tetrahedron Lett. 1990, 31, 977. Polyhydroxyamino acids: (h) Banick, B. K.; Manhas, M. S.; Bose, A. K. J. Org. Chem. 1993, 58, 307. γ-Keto α-amino acids: Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Smith, M. L.; Russel, A. T. Synlett 1993, 51. (j) Baldwin, J. E.; Adlington, R. M.; Rusell, A. T.; Smith, M. L. Tetrahedron Lett. 1995, 57, 4733. Prolines: (k) Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Vaughan, J. G. J. Chem. Soc., Chem. Commun. 1993, 1434. Baldwin, J. E.; Rudolph, M. Tetrahedron Lett. 1994, 35, 6163. Aminosugars: (m) Ha, D.-C.; Hart, D. J. Tetrahedron Lett. 1987, 28, 4489. (n) Shiozaki, M.; Ishida, N.; Sato, S. Bull. Chem. Soc. Jpn. 1989, 62, 3950. (o) Galluci, J. C.; Ha, D.-C.; Hart, D. J. Tetrahedron 1989, 45, 1283. (p) Hauser, F. M.; Ellenberger, S. R.; Rhee, R. P. J. Org. Chem. 1987, 52, 5041. (q) Araki, K.; O'Toole, J. C.; Welch, J. T. Bioorg. Med. Chem. Lett. 1993, 3, 2457. (r) Bose, A. K.; Mathur, C.; Wagle, D. R.; Naqvi, R.; Manhas, M. S. Heterocycles 1994, 39, 491. Pyrrolizidines: (s) Cavanga, F.; Linkies, H.; Pietsch, H.; Reuschling, D. Angew. Chem., Int. Ed. Engl. 1980, 129. Pyrrolidines: (t) Bose, A. K.; Krishnan, L.; Wagle, D. R.; Manhas, M. S. Tetrahedron Lett. 1986, 27, 3955. Morfolines: (u) Wagle, D. R.; Monteleone, M. G.; Krishnan, L.; Manhas, M. S.; Bose, A. K. J. Chem. Soc., Chem. Commun. 1989, 8915.
38. For reviews of non-β-lactam products from azetidinone frameworks, see: (a) Manhas, M. S.; Wagle, D. R.; Chiang, J.; Bose, A. K. Heterocycles 1988, 27, 1755. (b) Hesse, M. In Ring Enlargement in Organic Synthesis; VCH: Weinheim, 1991; p 97. Amino acids and peptides: (c) Ojima, I. In The Organic Chemistry of β-Lactams; Georg, G. I., Ed., VCH: New York, 1992; p 197. (d) Ojima, I. Acc. Chem. Res. 1995, 28, 383. (e) Hegedus, L. S. Acc. Chem. Res. 1995, 28, 299. Aspartic acids: (f) Hanessian, S.; Sumi, K.; Vanasse, B. Synlett 1992, 23. α,β-Diamino acids: (g) Ojima, I.; Pei, Y. Tetrahedron Lett. 1990, 31, 977. Polyhydroxyamino acids: (h) Banick, B. K.; Manhas, M. S.; Bose, A. K. J. Org. Chem. 1993, 58, 307. γ-Keto α-amino acids: Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Smith, M. L.; Russel, A. T. Synlett 1993, 51. (j) Baldwin, J. E.; Adlington, R. M.; Rusell, A. T.; Smith, M. L. Tetrahedron Lett. 1995, 57, 4733. Prolines: (k) Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Vaughan, J. G. J. Chem. Soc., Chem. Commun. 1993, 1434. Baldwin, J. E.; Rudolph, M. Tetrahedron Lett. 1994, 35, 6163. Aminosugars: (m) Ha, D.-C.; Hart, D. J. Tetrahedron Lett. 1987, 28, 4489. (n) Shiozaki, M.; Ishida, N.; Sato, S. Bull. Chem. Soc. Jpn. 1989, 62, 3950. (o) Galluci, J. C.; Ha, D.-C.; Hart, D. J. Tetrahedron 1989, 45, 1283. (p) Hauser, F. M.; Ellenberger, S. R.; Rhee, R. P. J. Org. Chem. 1987, 52, 5041. (q) Araki, K.; O'Toole, J. C.; Welch, J. T. Bioorg. Med. Chem. Lett. 1993, 3, 2457. (r) Bose, A. K.; Mathur, C.; Wagle, D. R.; Naqvi, R.; Manhas, M. S. Heterocycles 1994, 39, 491. Pyrrolizidines: (s) Cavanga, F.; Linkies, H.; Pietsch, H.; Reuschling, D. Angew. Chem., Int. Ed. Engl. 1980, 129. Pyrrolidines: (t) Bose, A. K.; Krishnan, L.; Wagle, D. R.; Manhas, M. S. Tetrahedron Lett. 1986, 27, 3955. Morfolines: (u) Wagle, D. R.; Monteleone, M. G.; Krishnan, L.; Manhas, M. S.; Bose, A. K. J. Chem. Soc., Chem. Commun. 1989, 8915.
39. For reviews of non-β-lactam products from azetidinone frameworks, see: (a) Manhas, M. S.; Wagle, D. R.; Chiang, J.; Bose, A. K. Heterocycles 1988, 27, 1755. (b) Hesse, M. In Ring Enlargement in Organic Synthesis; VCH: Weinheim, 1991; p 97. Amino acids and peptides: (c) Ojima, I. In The Organic Chemistry of β-Lactams; Georg, G. I., Ed., VCH: New York, 1992; p 197. (d) Ojima, I. Acc. Chem. Res. 1995, 28, 383. (e) Hegedus, L. S. Acc. Chem. Res. 1995, 28, 299. Aspartic acids: (f) Hanessian, S.; Sumi, K.; Vanasse, B. Synlett 1992, 23. α,β-Diamino acids: (g) Ojima, I.; Pei, Y. Tetrahedron Lett. 1990, 31, 977. Polyhydroxyamino acids: (h) Banick, B. K.; Manhas, M. S.; Bose, A. K. J. Org. Chem. 1993, 58, 307. γ-Keto α-amino acids: Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Smith, M. L.; Russel, A. T. Synlett 1993, 51. (j) Baldwin, J. E.; Adlington, R. M.; Rusell, A. T.; Smith, M. L. Tetrahedron Lett. 1995, 57, 4733. Prolines: (k) Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Vaughan, J. G. J. Chem. Soc., Chem. Commun. 1993, 1434. Baldwin, J. E.; Rudolph, M. Tetrahedron Lett. 1994, 35, 6163. Aminosugars: (m) Ha, D.-C.; Hart, D. J. Tetrahedron Lett. 1987, 28, 4489. (n) Shiozaki, M.; Ishida, N.; Sato, S. Bull. Chem. Soc. Jpn. 1989, 62, 3950. (o) Galluci, J. C.; Ha, D.-C.; Hart, D. J. Tetrahedron 1989, 45, 1283. (p) Hauser, F. M.; Ellenberger, S. R.; Rhee, R. P. J. Org. Chem. 1987, 52, 5041. (q) Araki, K.; O'Toole, J. C.; Welch, J. T. Bioorg. Med. Chem. Lett. 1993, 3, 2457. (r) Bose, A. K.; Mathur, C.; Wagle, D. R.; Naqvi, R.; Manhas, M. S. Heterocycles 1994, 39, 491. Pyrrolizidines: (s) Cavanga, F.; Linkies, H.; Pietsch, H.; Reuschling, D. Angew. Chem., Int. Ed. Engl. 1980, 129. Pyrrolidines: (t) Bose, A. K.; Krishnan, L.; Wagle, D. R.; Manhas, M. S. Tetrahedron Lett. 1986, 27, 3955. Morfolines: (u) Wagle, D. R.; Monteleone, M. G.; Krishnan, L.; Manhas, M. S.; Bose, A. K. J. Chem. Soc., Chem. Commun. 1989, 8915.
40. For reviews of non-β-lactam products from azetidinone frameworks, see: (a) Manhas, M. S.; Wagle, D. R.; Chiang, J.; Bose, A. K. Heterocycles 1988, 27, 1755. (b) Hesse, M. In Ring Enlargement in Organic Synthesis; VCH: Weinheim, 1991; p 97. Amino acids and peptides: (c) Ojima, I. In The Organic Chemistry of β-Lactams; Georg, G. I., Ed., VCH: New York, 1992; p 197. (d) Ojima, I. Acc. Chem. Res. 1995, 28, 383. (e) Hegedus, L. S. Acc. Chem. Res. 1995, 28, 299. Aspartic acids: (f) Hanessian, S.; Sumi, K.; Vanasse, B. Synlett 1992, 23. α,β-Diamino acids: (g) Ojima, I.; Pei, Y. Tetrahedron Lett. 1990, 31, 977. Polyhydroxyamino acids: (h) Banick, B. K.; Manhas, M. S.; Bose, A. K. J. Org. Chem. 1993, 58, 307. γ-Keto α-amino acids: Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Smith, M. L.; Russel, A. T. Synlett 1993, 51. (j) Baldwin, J. E.; Adlington, R. M.; Rusell, A. T.; Smith, M. L. Tetrahedron Lett. 1995, 57, 4733. Prolines: (k) Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Vaughan, J. G. J. Chem. Soc., Chem. Commun. 1993, 1434. Baldwin, J. E.; Rudolph, M. Tetrahedron Lett. 1994, 35, 6163. Aminosugars: (m) Ha, D.-C.; Hart, D. J. Tetrahedron Lett. 1987, 28, 4489. (n) Shiozaki, M.; Ishida, N.; Sato, S. Bull. Chem. Soc. Jpn. 1989, 62, 3950. (o) Galluci, J. C.; Ha, D.-C.; Hart, D. J. Tetrahedron 1989, 45, 1283. (p) Hauser, F. M.; Ellenberger, S. R.; Rhee, R. P. J. Org. Chem. 1987, 52, 5041. (q) Araki, K.; O'Toole, J. C.; Welch, J. T. Bioorg. Med. Chem. Lett. 1993, 3, 2457. (r) Bose, A. K.; Mathur, C.; Wagle, D. R.; Naqvi, R.; Manhas, M. S. Heterocycles 1994, 39, 491. Pyrrolizidines: (s) Cavanga, F.; Linkies, H.; Pietsch, H.; Reuschling, D. Angew. Chem., Int. Ed. Engl. 1980, 129. Pyrrolidines: (t) Bose, A. K.; Krishnan, L.; Wagle, D. R.; Manhas, M. S. Tetrahedron Lett. 1986, 27, 3955. Morfolines: (u) Wagle, D. R.; Monteleone, M. G.; Krishnan, L.; Manhas, M. S.; Bose, A. K. J. Chem. Soc., Chem. Commun. 1989, 8915.
41. For reviews of non-β-lactam products from azetidinone frameworks, see: (a) Manhas, M. S.; Wagle, D. R.; Chiang, J.; Bose, A. K. Heterocycles 1988, 27, 1755. (b) Hesse, M. In Ring Enlargement in Organic Synthesis; VCH: Weinheim, 1991; p 97. Amino acids and peptides: (c) Ojima, I. In The Organic Chemistry of β-Lactams; Georg, G. I., Ed., VCH: New York, 1992; p 197. (d) Ojima, I. Acc. Chem. Res. 1995, 28, 383. (e) Hegedus, L. S. Acc. Chem. Res. 1995, 28, 299. Aspartic acids: (f) Hanessian, S.; Sumi, K.; Vanasse, B. Synlett 1992, 23. α,β-Diamino acids: (g) Ojima, I.; Pei, Y. Tetrahedron Lett. 1990, 31, 977. Polyhydroxyamino acids: (h) Banick, B. K.; Manhas, M. S.; Bose, A. K. J. Org. Chem. 1993, 58, 307. γ-Keto α-amino acids: Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Smith, M. L.; Russel, A. T. Synlett 1993, 51. (j) Baldwin, J. E.; Adlington, R. M.; Rusell, A. T.; Smith, M. L. Tetrahedron Lett. 1995, 57, 4733. Prolines: (k) Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Vaughan, J. G. J. Chem. Soc., Chem. Commun. 1993, 1434. Baldwin, J. E.; Rudolph, M. Tetrahedron Lett. 1994, 35, 6163. Aminosugars: (m) Ha, D.-C.; Hart, D. J. Tetrahedron Lett. 1987, 28, 4489. (n) Shiozaki, M.; Ishida, N.; Sato, S. Bull. Chem. Soc. Jpn. 1989, 62, 3950. (o) Galluci, J. C.; Ha, D.-C.; Hart, D. J. Tetrahedron 1989, 45, 1283. (p) Hauser, F. M.; Ellenberger, S. R.; Rhee, R. P. J. Org. Chem. 1987, 52, 5041. (q) Araki, K.; O'Toole, J. C.; Welch, J. T. Bioorg. Med. Chem. Lett. 1993, 3, 2457. (r) Bose, A. K.; Mathur, C.; Wagle, D. R.; Naqvi, R.; Manhas, M. S. Heterocycles 1994, 39, 491. Pyrrolizidines: (s) Cavanga, F.; Linkies, H.; Pietsch, H.; Reuschling, D. Angew. Chem., Int. Ed. Engl. 1980, 129. Pyrrolidines: (t) Bose, A. K.; Krishnan, L.; Wagle, D. R.; Manhas, M. S. Tetrahedron Lett. 1986, 27, 3955. Morfolines: (u) Wagle, D. R.; Monteleone, M. G.; Krishnan, L.; Manhas, M. S.; Bose, A. K. J. Chem. Soc., Chem. Commun. 1989, 8915.
42. For reviews of non-β-lactam products from azetidinone frameworks, see: (a) Manhas, M. S.; Wagle, D. R.; Chiang, J.; Bose, A. K. Heterocycles 1988, 27, 1755. (b) Hesse, M. In Ring Enlargement in Organic Synthesis; VCH: Weinheim, 1991; p 97. Amino acids and peptides: (c) Ojima, I. In The Organic Chemistry of β-Lactams; Georg, G. I., Ed., VCH: New York, 1992; p 197. (d) Ojima, I. Acc. Chem. Res. 1995, 28, 383. (e) Hegedus, L. S. Acc. Chem. Res. 1995, 28, 299. Aspartic acids: (f) Hanessian, S.; Sumi, K.; Vanasse, B. Synlett 1992, 23. α,β-Diamino acids: (g) Ojima, I.; Pei, Y. Tetrahedron Lett. 1990, 31, 977. Polyhydroxyamino acids: (h) Banick, B. K.; Manhas, M. S.; Bose, A. K. J. Org. Chem. 1993, 58, 307. γ-Keto α-amino acids: Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Smith, M. L.; Russel, A. T. Synlett 1993, 51. (j) Baldwin, J. E.; Adlington, R. M.; Rusell, A. T.; Smith, M. L. Tetrahedron Lett. 1995, 57, 4733. Prolines: (k) Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Vaughan, J. G. J. Chem. Soc., Chem. Commun. 1993, 1434. Baldwin, J. E.; Rudolph, M. Tetrahedron Lett. 1994, 35, 6163. Aminosugars: (m) Ha, D.-C.; Hart, D. J. Tetrahedron Lett. 1987, 28, 4489. (n) Shiozaki, M.; Ishida, N.; Sato, S. Bull. Chem. Soc. Jpn. 1989, 62, 3950. (o) Galluci, J. C.; Ha, D.-C.; Hart, D. J. Tetrahedron 1989, 45, 1283. (p) Hauser, F. M.; Ellenberger, S. R.; Rhee, R. P. J. Org. Chem. 1987, 52, 5041. (q) Araki, K.; O'Toole, J. C.; Welch, J. T. Bioorg. Med. Chem. Lett. 1993, 3, 2457. (r) Bose, A. K.; Mathur, C.; Wagle, D. R.; Naqvi, R.; Manhas, M. S. Heterocycles 1994, 39, 491. Pyrrolizidines: (s) Cavanga, F.; Linkies, H.; Pietsch, H.; Reuschling, D. Angew. Chem., Int. Ed. Engl. 1980, 129. Pyrrolidines: (t) Bose, A. K.; Krishnan, L.; Wagle, D. R.; Manhas, M. S. Tetrahedron Lett. 1986, 27, 3955. Morfolines: (u) Wagle, D. R.; Monteleone, M. G.; Krishnan, L.; Manhas, M. S.; Bose, A. K. J. Chem. Soc., Chem. Commun. 1989, 8915.
43. For reviews of non-β-lactam products from azetidinone frameworks, see: (a) Manhas, M. S.; Wagle, D. R.; Chiang, J.; Bose, A. K. Heterocycles 1988, 27, 1755. (b) Hesse, M. In Ring Enlargement in Organic Synthesis; VCH: Weinheim, 1991; p 97. Amino acids and peptides: (c) Ojima, I. In The Organic Chemistry of β-Lactams; Georg, G. I., Ed., VCH: New York, 1992; p 197. (d) Ojima, I. Acc. Chem. Res. 1995, 28, 383. (e) Hegedus, L. S. Acc. Chem. Res. 1995, 28, 299. Aspartic acids: (f) Hanessian, S.; Sumi, K.; Vanasse, B. Synlett 1992, 23. α,β-Diamino acids: (g) Ojima, I.; Pei, Y. Tetrahedron Lett. 1990, 31, 977. Polyhydroxyamino acids: (h) Banick, B. K.; Manhas, M. S.; Bose, A. K. J. Org. Chem. 1993, 58, 307. γ-Keto α-amino acids: Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Smith, M. L.; Russel, A. T. Synlett 1993, 51. (j) Baldwin, J. E.; Adlington, R. M.; Rusell, A. T.; Smith, M. L. Tetrahedron Lett. 1995, 57, 4733. Prolines: (k) Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Vaughan, J. G. J. Chem. Soc., Chem. Commun. 1993, 1434. Baldwin, J. E.; Rudolph, M. Tetrahedron Lett. 1994, 35, 6163. Aminosugars: (m) Ha, D.-C.; Hart, D. J. Tetrahedron Lett. 1987, 28, 4489. (n) Shiozaki, M.; Ishida, N.; Sato, S. Bull. Chem. Soc. Jpn. 1989, 62, 3950. (o) Galluci, J. C.; Ha, D.-C.; Hart, D. J. Tetrahedron 1989, 45, 1283. (p) Hauser, F. M.; Ellenberger, S. R.; Rhee, R. P. J. Org. Chem. 1987, 52, 5041. (q) Araki, K.; O'Toole, J. C.; Welch, J. T. Bioorg. Med. Chem. Lett. 1993, 3, 2457. (r) Bose, A. K.; Mathur, C.; Wagle, D. R.; Naqvi, R.; Manhas, M. S. Heterocycles 1994, 39, 491. Pyrrolizidines: (s) Cavanga, F.; Linkies, H.; Pietsch, H.; Reuschling, D. Angew. Chem., Int. Ed. Engl. 1980, 129. Pyrrolidines: (t) Bose, A. K.; Krishnan, L.; Wagle, D. R.; Manhas, M. S. Tetrahedron Lett. 1986, 27, 3955. Morfolines: (u) Wagle, D. R.; Monteleone, M. G.; Krishnan, L.; Manhas, M. S.; Bose, A. K. J. Chem. Soc., Chem. Commun. 1989, 8915.
44. For reviews of non-β-lactam products from azetidinone frameworks, see: (a) Manhas, M. S.; Wagle, D. R.; Chiang, J.; Bose, A. K. Heterocycles 1988, 27, 1755. (b) Hesse, M. In Ring Enlargement in Organic Synthesis; VCH: Weinheim, 1991; p 97. Amino acids and peptides: (c) Ojima, I. In The Organic Chemistry of β-Lactams; Georg, G. I., Ed., VCH: New York, 1992; p 197. (d) Ojima, I. Acc. Chem. Res. 1995, 28, 383. (e) Hegedus, L. S. Acc. Chem. Res. 1995, 28, 299. Aspartic acids: (f) Hanessian, S.; Sumi, K.; Vanasse, B. Synlett 1992, 23. α,β-Diamino acids: (g) Ojima, I.; Pei, Y. Tetrahedron Lett. 1990, 31, 977. Polyhydroxyamino acids: (h) Banick, B. K.; Manhas, M. S.; Bose, A. K. J. Org. Chem. 1993, 58, 307. γ-Keto α-amino acids: Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Smith, M. L.; Russel, A. T. Synlett 1993, 51. (j) Baldwin, J. E.; Adlington, R. M.; Rusell, A. T.; Smith, M. L. Tetrahedron Lett. 1995, 57, 4733. Prolines: (k) Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Vaughan, J. G. J. Chem. Soc., Chem. Commun. 1993, 1434. Baldwin, J. E.; Rudolph, M. Tetrahedron Lett. 1994, 35, 6163. Aminosugars: (m) Ha, D.-C.; Hart, D. J. Tetrahedron Lett. 1987, 28, 4489. (n) Shiozaki, M.; Ishida, N.; Sato, S. Bull. Chem. Soc. Jpn. 1989, 62, 3950. (o) Galluci, J. C.; Ha, D.-C.; Hart, D. J. Tetrahedron 1989, 45, 1283. (p) Hauser, F. M.; Ellenberger, S. R.; Rhee, R. P. J. Org. Chem. 1987, 52, 5041. (q) Araki, K.; O'Toole, J. C.; Welch, J. T. Bioorg. Med. Chem. Lett. 1993, 3, 2457. (r) Bose, A. K.; Mathur, C.; Wagle, D. R.; Naqvi, R.; Manhas, M. S. Heterocycles 1994, 39, 491. Pyrrolizidines: (s) Cavanga, F.; Linkies, H.; Pietsch, H.; Reuschling, D. Angew. Chem., Int. Ed. Engl. 1980, 129. Pyrrolidines: (t) Bose, A. K.; Krishnan, L.; Wagle, D. R.; Manhas, M. S. Tetrahedron Lett. 1986, 27, 3955. Morfolines: (u) Wagle, D. R.; Monteleone, M. G.; Krishnan, L.; Manhas, M. S.; Bose, A. K. J. Chem. Soc., Chem. Commun. 1989, 8915.
45. For reviews of non-β-lactam products from azetidinone frameworks, see: (a) Manhas, M. S.; Wagle, D. R.; Chiang, J.; Bose, A. K. Heterocycles 1988, 27, 1755. (b) Hesse, M. In Ring Enlargement in Organic Synthesis; VCH: Weinheim, 1991; p 97. Amino acids and peptides: (c) Ojima, I. In The Organic Chemistry of β-Lactams; Georg, G. I., Ed., VCH: New York, 1992; p 197. (d) Ojima, I. Acc. Chem. Res. 1995, 28, 383. (e) Hegedus, L. S. Acc. Chem. Res. 1995, 28, 299. Aspartic acids: (f) Hanessian, S.; Sumi, K.; Vanasse, B. Synlett 1992, 23. α,β-Diamino acids: (g) Ojima, I.; Pei, Y. Tetrahedron Lett. 1990, 31, 977. Polyhydroxyamino acids: (h) Banick, B. K.; Manhas, M. S.; Bose, A. K. J. Org. Chem. 1993, 58, 307. γ-Keto α-amino acids: Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Smith, M. L.; Russel, A. T. Synlett 1993, 51. (j) Baldwin, J. E.; Adlington, R. M.; Rusell, A. T.; Smith, M. L. Tetrahedron Lett. 1995, 57, 4733. Prolines: (k) Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Vaughan, J. G. J. Chem. Soc., Chem. Commun. 1993, 1434. Baldwin, J. E.; Rudolph, M. Tetrahedron Lett. 1994, 35, 6163. Aminosugars: (m) Ha, D.-C.; Hart, D. J. Tetrahedron Lett. 1987, 28, 4489. (n) Shiozaki, M.; Ishida, N.; Sato, S. Bull. Chem. Soc. Jpn. 1989, 62, 3950. (o) Galluci, J. C.; Ha, D.-C.; Hart, D. J. Tetrahedron 1989, 45, 1283. (p) Hauser, F. M.; Ellenberger, S. R.; Rhee, R. P. J. Org. Chem. 1987, 52, 5041. (q) Araki, K.; O'Toole, J. C.; Welch, J. T. Bioorg. Med. Chem. Lett. 1993, 3, 2457. (r) Bose, A. K.; Mathur, C.; Wagle, D. R.; Naqvi, R.; Manhas, M. S. Heterocycles 1994, 39, 491. Pyrrolizidines: (s) Cavanga, F.; Linkies, H.; Pietsch, H.; Reuschling, D. Angew. Chem., Int. Ed. Engl. 1980, 129. Pyrrolidines: (t) Bose, A. K.; Krishnan, L.; Wagle, D. R.; Manhas, M. S. Tetrahedron Lett. 1986, 27, 3955. Morfolines: (u) Wagle, D. R.; Monteleone, M. G.; Krishnan, L.; Manhas, M. S.; Bose, A. K. J. Chem. Soc., Chem. Commun. 1989, 8915.
46. For reviews of non-β-lactam products from azetidinone frameworks, see: (a) Manhas, M. S.; Wagle, D. R.; Chiang, J.; Bose, A. K. Heterocycles 1988, 27, 1755. (b) Hesse, M. In Ring Enlargement in Organic Synthesis; VCH: Weinheim, 1991; p 97. Amino acids and peptides: (c) Ojima, I. In The Organic Chemistry of β-Lactams; Georg, G. I., Ed., VCH: New York, 1992; p 197. (d) Ojima, I. Acc. Chem. Res. 1995, 28, 383. (e) Hegedus, L. S. Acc. Chem. Res. 1995, 28, 299. Aspartic acids: (f) Hanessian, S.; Sumi, K.; Vanasse, B. Synlett 1992, 23. α,β-Diamino acids: (g) Ojima, I.; Pei, Y. Tetrahedron Lett. 1990, 31, 977. Polyhydroxyamino acids: (h) Banick, B. K.; Manhas, M. S.; Bose, A. K. J. Org. Chem. 1993, 58, 307. γ-Keto α-amino acids: Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Smith, M. L.; Russel, A. T. Synlett 1993, 51. (j) Baldwin, J. E.; Adlington, R. M.; Rusell, A. T.; Smith, M. L. Tetrahedron Lett. 1995, 57, 4733. Prolines: (k) Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Vaughan, J. G. J. Chem. Soc., Chem. Commun. 1993, 1434. Baldwin, J. E.; Rudolph, M. Tetrahedron Lett. 1994, 35, 6163. Aminosugars: (m) Ha, D.-C.; Hart, D. J. Tetrahedron Lett. 1987, 28, 4489. (n) Shiozaki, M.; Ishida, N.; Sato, S. Bull. Chem. Soc. Jpn. 1989, 62, 3950. (o) Galluci, J. C.; Ha, D.-C.; Hart, D. J. Tetrahedron 1989, 45, 1283. (p) Hauser, F. M.; Ellenberger, S. R.; Rhee, R. P. J. Org. Chem. 1987, 52, 5041. (q) Araki, K.; O'Toole, J. C.; Welch, J. T. Bioorg. Med. Chem. Lett. 1993, 3, 2457. (r) Bose, A. K.; Mathur, C.; Wagle, D. R.; Naqvi, R.; Manhas, M. S. Heterocycles 1994, 39, 491. Pyrrolizidines: (s) Cavanga, F.; Linkies, H.; Pietsch, H.; Reuschling, D. Angew. Chem., Int. Ed. Engl. 1980, 129. Pyrrolidines: (t) Bose, A. K.; Krishnan, L.; Wagle, D. R.; Manhas, M. S. Tetrahedron Lett. 1986, 27, 3955. Morfolines: (u) Wagle, D. R.; Monteleone, M. G.; Krishnan, L.; Manhas, M. S.; Bose, A. K. J. Chem. Soc., Chem. Commun. 1989, 8915.
47. For reviews of non-β-lactam products from azetidinone frameworks, see: (a) Manhas, M. S.; Wagle, D. R.; Chiang, J.; Bose, A. K. Heterocycles 1988, 27, 1755. (b) Hesse, M. In Ring Enlargement in Organic Synthesis; VCH: Weinheim, 1991; p 97. Amino acids and peptides: (c) Ojima, I. In The Organic Chemistry of β-Lactams; Georg, G. I., Ed., VCH: New York, 1992; p 197. (d) Ojima, I. Acc. Chem. Res. 1995, 28, 383. (e) Hegedus, L. S. Acc. Chem. Res. 1995, 28, 299. Aspartic acids: (f) Hanessian, S.; Sumi, K.; Vanasse, B. Synlett 1992, 23. α,β-Diamino acids: (g) Ojima, I.; Pei, Y. Tetrahedron Lett. 1990, 31, 977. Polyhydroxyamino acids: (h) Banick, B. K.; Manhas, M. S.; Bose, A. K. J. Org. Chem. 1993, 58, 307. γ-Keto α-amino acids: Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Smith, M. L.; Russel, A. T. Synlett 1993, 51. (j) Baldwin, J. E.; Adlington, R. M.; Rusell, A. T.; Smith, M. L. Tetrahedron Lett. 1995, 57, 4733. Prolines: (k) Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Vaughan, J. G. J. Chem. Soc., Chem. Commun. 1993, 1434. Baldwin, J. E.; Rudolph, M. Tetrahedron Lett. 1994, 35, 6163. Aminosugars: (m) Ha, D.-C.; Hart, D. J. Tetrahedron Lett. 1987, 28, 4489. (n) Shiozaki, M.; Ishida, N.; Sato, S. Bull. Chem. Soc. Jpn. 1989, 62, 3950. (o) Galluci, J. C.; Ha, D.-C.; Hart, D. J. Tetrahedron 1989, 45, 1283. (p) Hauser, F. M.; Ellenberger, S. R.; Rhee, R. P. J. Org. Chem. 1987, 52, 5041. (q) Araki, K.; O'Toole, J. C.; Welch, J. T. Bioorg. Med. Chem. Lett. 1993, 3, 2457. (r) Bose, A. K.; Mathur, C.; Wagle, D. R.; Naqvi, R.; Manhas, M. S. Heterocycles 1994, 39, 491. Pyrrolizidines: (s) Cavanga, F.; Linkies, H.; Pietsch, H.; Reuschling, D. Angew. Chem., Int. Ed. Engl. 1980, 129. Pyrrolidines: (t) Bose, A. K.; Krishnan, L.; Wagle, D. R.; Manhas, M. S. Tetrahedron Lett. 1986, 27, 3955. Morfolines: (u) Wagle, D. R.; Monteleone, M. G.; Krishnan, L.; Manhas, M. S.; Bose, A. K. J. Chem. Soc., Chem. Commun. 1989, 8915.
48. For reviews of non-β-lactam products from azetidinone frameworks, see: (a) Manhas, M. S.; Wagle, D. R.; Chiang, J.; Bose, A. K. Heterocycles 1988, 27, 1755. (b) Hesse, M. In Ring Enlargement in Organic Synthesis; VCH: Weinheim, 1991; p 97. Amino acids and peptides: (c) Ojima, I. In The Organic Chemistry of β-Lactams; Georg, G. I., Ed., VCH: New York, 1992; p 197. (d) Ojima, I. Acc. Chem. Res. 1995, 28, 383. (e) Hegedus, L. S. Acc. Chem. Res. 1995, 28, 299. Aspartic acids: (f) Hanessian, S.; Sumi, K.; Vanasse, B. Synlett 1992, 23. α,β-Diamino acids: (g) Ojima, I.; Pei, Y. Tetrahedron Lett. 1990, 31, 977. Polyhydroxyamino acids: (h) Banick, B. K.; Manhas, M. S.; Bose, A. K. J. Org. Chem. 1993, 58, 307. γ-Keto α-amino acids: Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Smith, M. L.; Russel, A. T. Synlett 1993, 51. (j) Baldwin, J. E.; Adlington, R. M.; Rusell, A. T.; Smith, M. L. Tetrahedron Lett. 1995, 57, 4733. Prolines: (k) Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Vaughan, J. G. J. Chem. Soc., Chem. Commun. 1993, 1434. Baldwin, J. E.; Rudolph, M. Tetrahedron Lett. 1994, 35, 6163. Aminosugars: (m) Ha, D.-C.; Hart, D. J. Tetrahedron Lett. 1987, 28, 4489. (n) Shiozaki, M.; Ishida, N.; Sato, S. Bull. Chem. Soc. Jpn. 1989, 62, 3950. (o) Galluci, J. C.; Ha, D.-C.; Hart, D. J. Tetrahedron 1989, 45, 1283. (p) Hauser, F. M.; Ellenberger, S. R.; Rhee, R. P. J. Org. Chem. 1987, 52, 5041. (q) Araki, K.; O'Toole, J. C.; Welch, J. T. Bioorg. Med. Chem. Lett. 1993, 3, 2457. (r) Bose, A. K.; Mathur, C.; Wagle, D. R.; Naqvi, R.; Manhas, M. S. Heterocycles 1994, 39, 491. Pyrrolizidines: (s) Cavanga, F.; Linkies, H.; Pietsch, H.; Reuschling, D. Angew. Chem., Int. Ed. Engl. 1980, 129. Pyrrolidines: (t) Bose, A. K.; Krishnan, L.; Wagle, D. R.; Manhas, M. S. Tetrahedron Lett. 1986, 27, 3955. Morfolines: (u) Wagle, D. R.; Monteleone, M. G.; Krishnan, L.; Manhas, M. S.; Bose, A. K. J. Chem. Soc., Chem. Commun. 1989, 8915.
49. For reviews of non-β-lactam products from azetidinone frameworks, see: (a) Manhas, M. S.; Wagle, D. R.; Chiang, J.; Bose, A. K. Heterocycles 1988, 27, 1755. (b) Hesse, M. In Ring Enlargement in Organic Synthesis; VCH: Weinheim, 1991; p 97. Amino acids and peptides: (c) Ojima, I. In The Organic Chemistry of β-Lactams; Georg, G. I., Ed., VCH: New York, 1992; p 197. (d) Ojima, I. Acc. Chem. Res. 1995, 28, 383. (e) Hegedus, L. S. Acc. Chem. Res. 1995, 28, 299. Aspartic acids: (f) Hanessian, S.; Sumi, K.; Vanasse, B. Synlett 1992, 23. α,β-Diamino acids: (g) Ojima, I.; Pei, Y. Tetrahedron Lett. 1990, 31, 977. Polyhydroxyamino acids: (h) Banick, B. K.; Manhas, M. S.; Bose, A. K. J. Org. Chem. 1993, 58, 307. γ-Keto α-amino acids: Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Smith, M. L.; Russel, A. T. Synlett 1993, 51. (j) Baldwin, J. E.; Adlington, R. M.; Rusell, A. T.; Smith, M. L. Tetrahedron Lett. 1995, 57, 4733. Prolines: (k) Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Vaughan, J. G. J. Chem. Soc., Chem. Commun. 1993, 1434. Baldwin, J. E.; Rudolph, M. Tetrahedron Lett. 1994, 35, 6163. Aminosugars: (m) Ha, D.-C.; Hart, D. J. Tetrahedron Lett. 1987, 28, 4489. (n) Shiozaki, M.; Ishida, N.; Sato, S. Bull. Chem. Soc. Jpn. 1989, 62, 3950. (o) Galluci, J. C.; Ha, D.-C.; Hart, D. J. Tetrahedron 1989, 45, 1283. (p) Hauser, F. M.; Ellenberger, S. R.; Rhee, R. P. J. Org. Chem. 1987, 52, 5041. (q) Araki, K.; O'Toole, J. C.; Welch, J. T. Bioorg. Med. Chem. Lett. 1993, 3, 2457. (r) Bose, A. K.; Mathur, C.; Wagle, D. R.; Naqvi, R.; Manhas, M. S. Heterocycles 1994, 39, 491. Pyrrolizidines: (s) Cavanga, F.; Linkies, H.; Pietsch, H.; Reuschling, D. Angew. Chem., Int. Ed. Engl. 1980, 129. Pyrrolidines: (t) Bose, A. K.; Krishnan, L.; Wagle, D. R.; Manhas, M. S. Tetrahedron Lett. 1986, 27, 3955. Morfolines: (u) Wagle, D. R.; Monteleone, M. G.; Krishnan, L.; Manhas, M. S.; Bose, A. K. J. Chem. Soc., Chem. Commun. 1989, 8915.
50. For reviews of non-β-lactam products from azetidinone frameworks, see: (a) Manhas, M. S.; Wagle, D. R.; Chiang, J.; Bose, A. K. Heterocycles 1988, 27, 1755. (b) Hesse, M. In Ring Enlargement in Organic Synthesis; VCH: Weinheim, 1991; p 97. Amino acids and peptides: (c) Ojima, I. In The Organic Chemistry of β-Lactams; Georg, G. I., Ed., VCH: New York, 1992; p 197. (d) Ojima, I. Acc. Chem. Res. 1995, 28, 383. (e) Hegedus, L. S. Acc. Chem. Res. 1995, 28, 299. Aspartic acids: (f) Hanessian, S.; Sumi, K.; Vanasse, B. Synlett 1992, 23. α,β-Diamino acids: (g) Ojima, I.; Pei, Y. Tetrahedron Lett. 1990, 31, 977. Polyhydroxyamino acids: (h) Banick, B. K.; Manhas, M. S.; Bose, A. K. J. Org. Chem. 1993, 58, 307. γ-Keto α-amino acids: Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Smith, M. L.; Russel, A. T. Synlett 1993, 51. (j) Baldwin, J. E.; Adlington, R. M.; Rusell, A. T.; Smith, M. L. Tetrahedron Lett. 1995, 57, 4733. Prolines: (k) Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Vaughan, J. G. J. Chem. Soc., Chem. Commun. 1993, 1434. Baldwin, J. E.; Rudolph, M. Tetrahedron Lett. 1994, 35,
51. For reviews of non-β-lactam products from azetidinone frameworks, see: (a) Manhas, M. S.; Wagle, D. R.; Chiang, J.; Bose, A. K. Heterocycles 1988, 27, 1755. (b) Hesse, M. In Ring Enlargement in Organic Synthesis; VCH: Weinheim, 1991; p 97. Amino acids and peptides: (c) Ojima, I. In The Organic Chemistry of β-Lactams; Georg, G. I., Ed., VCH: New York, 1992; p 197. (d) Ojima, I. Acc. Chem. Res. 1995, 28, 383. (e) Hegedus, L. S. Acc. Chem. Res. 1995, 28, 299. Aspartic acids: (f) Hanessian, S.; Sumi, K.; Vanasse, B. Synlett 1992, 23. α,β-Diamino acids: (g) Ojima, I.; Pei, Y. Tetrahedron Lett. 1990, 31, 977. Polyhydroxyamino acids: (h) Banick, B. K.; Manhas, M. S.; Bose, A. K. J. Org. Chem. 1993, 58, 307. γ-Keto α-amino acids: Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Smith, M. L.; Russel, A. T. Synlett 1993, 51. (j) Baldwin, J. E.; Adlington, R. M.; Rusell, A. T.; Smith, M. L. Tetrahedron Lett. 1995, 57, 4733. Prolines: (k) Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Vaughan, J. G. J. Chem. Soc., Chem. Commun. 1993, 1434. Baldwin, J. E.; Rudolph, M. Tetrahedron Lett. 1994, 35, 6163. Aminosugars: (m) Ha, D.-C.; Hart, D. J. Tetrahedron Lett. 1987, 28, 4489. (n) Shiozaki, M.; Ishida, N.; Sato, S. Bull. Chem. Soc. Jpn. 1989, 62, 3950. (o) Galluci, J. C.; Ha, D.-C.; Hart, D. J. Tetrahedron 1989, 45, 1283. (p) Hauser, F. M.; Ellenberger, S. R.; Rhee, R. P. J. Org. Chem. 1987, 52, 5041. (q) Araki, K.; O'Toole, J. C.; Welch, J. T. Bioorg. Med. Chem. Lett. 1993, 3, 2457. (r) Bose, A. K.; Mathur, C.; Wagle, D. R.; Naqvi, R.; Manhas, M. S. Heterocycles 1994, 39, 491. Pyrrolizidines: (s) Cavanga, F.; Linkies, H.; Pietsch, H.; Reuschling, D. Angew. Chem., Int. Ed. Engl. 1980, 129. Pyrrolidines: (t) Bose, A. K.; Krishnan, L.; Wagle, D. R.; Manhas, M. S. Tetrahedron Lett. 1986, 27, 3955. Morfolines: (u) Wagle, D. R.; Monteleone, M. G.; Krishnan, L.; Manhas, M. S.; Bose, A. K. J. Chem. Soc., Chem. Commun. 1989, 8915.
52. For reviews of non-β-lactam products from azetidinone frameworks, see: (a) Manhas, M. S.; Wagle, D. R.; Chiang, J.; Bose, A. K. Heterocycles 1988, 27, 1755. (b) Hesse, M. In Ring Enlargement in Organic Synthesis; VCH: Weinheim, 1991; p 97. Amino acids and peptides: (c) Ojima, I. In The Organic Chemistry of β-Lactams; Georg, G. I., Ed., VCH: New York, 1992; p 197. (d) Ojima, I. Acc. Chem. Res. 1995, 28, 383. (e) Hegedus, L. S. Acc. Chem. Res. 1995, 28, 299. Aspartic acids: (f) Hanessian, S.; Sumi, K.; Vanasse, B. Synlett 1992, 23. α,β-Diamino acids: (g) Ojima, I.; Pei, Y. Tetrahedron Lett. 1990, 31, 977. Polyhydroxyamino acids: (h) Banick, B. K.; Manhas, M. S.; Bose, A. K. J. Org. Chem. 1993, 58, 307. γ-Keto α-amino acids: Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Smith, M. L.; Russel, A. T. Synlett 1993, 51. (j) Baldwin, J. E.; Adlington, R. M.; Rusell, A. T.; Smith, M. L. Tetrahedron Lett. 1995, 57, 4733. Prolines: (k) Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Vaughan, J. G. J. Chem. Soc., Chem. Commun. 1993, 1434. Baldwin, J. E.; Rudolph, M. Tetrahedron Lett. 1994, 35, 6163. Aminosugars: (m) Ha, D.-C.; Hart, D. J. Tetrahedron Lett. 1987, 28, 4489. (n) Shiozaki, M.; Ishida, N.; Sato, S. Bull. Chem. Soc. Jpn. 1989, 62, 3950. (o) Galluci, J. C.; Ha, D.-C.; Hart, D. J. Tetrahedron 1989, 45, 1283. (p) Hauser, F. M.; Ellenberger, S. R.; Rhee, R. P. J. Org. Chem. 1987, 52, 5041. (q) Araki, K.; O'Toole, J. C.; Welch, J. T. Bioorg. Med. Chem. Lett. 1993, 3, 2457. (r) Bose, A. K.; Mathur, C.; Wagle, D. R.; Naqvi, R.; Manhas, M. S. Heterocycles 1994, 39, 491. Pyrrolizidines: (s) Cavanga, F.; Linkies, H.; Pietsch, H.; Reuschling, D. Angew. Chem., Int. Ed. Engl. 1980, 129. Pyrrolidines: (t) Bose, A. K.; Krishnan, L.; Wagle, D. R.; Manhas, M. S. Tetrahedron Lett. 1986, 27, 3955. Morfolines: (u) Wagle, D. R.; Monteleone, M. G.; Krishnan, L.; Manhas, M. S.; Bose, A. K. J. Chem. Soc., Chem. Commun. 1989, 8915.
53. For reviews of non-β-lactam products from azetidinone frameworks, see: (a) Manhas, M. S.; Wagle, D. R.; Chiang, J.; Bose, A. K. Heterocycles 1988, 27, 1755. (b) Hesse, M. In Ring Enlargement in Organic Synthesis; VCH: Weinheim, 1991; p 97. Amino acids and peptides: (c) Ojima, I. In The Organic Chemistry of β-Lactams; Georg, G. I., Ed., VCH: New York, 1992; p 197. (d) Ojima, I. Acc. Chem. Res. 1995, 28, 383. (e) Hegedus, L. S. Acc. Chem. Res. 1995, 28, 299. Aspartic acids: (f) Hanessian, S.; Sumi, K.; Vanasse, B. Synlett 1992, 23. α,β-Diamino acids: (g) Ojima, I.; Pei, Y. Tetrahedron Lett. 1990, 31, 977. Polyhydroxyamino acids: (h) Banick, B. K.; Manhas, M. S.; Bose, A. K. J. Org. Chem. 1993, 58, 307. γ-Keto α-amino acids: Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Smith, M. L.; Russel, A. T. Synlett 1993, 51. (j) Baldwin, J. E.; Adlington, R. M.; Rusell, A. T.; Smith, M. L. Tetrahedron Lett. 1995, 57, 4733. Prolines: (k) Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Vaughan, J. G. J. Chem. Soc., Chem. Commun. 1993, 1434. Baldwin, J. E.; Rudolph, M. Tetrahedron Lett. 1994, 35, 6163. Aminosugars: (m) Ha, D.-C.; Hart, D. J. Tetrahedron Lett. 1987, 28, 4489. (n) Shiozaki, M.; Ishida, N.; Sato, S. Bull. Chem. Soc. Jpn. 1989, 62, 3950. (o) Galluci, J. C.; Ha, D.-C.; Hart, D. J. Tetrahedron 1989, 45, 1283. (p) Hauser, F. M.; Ellenberger, S. R.; Rhee, R. P. J. Org. Chem. 1987, 52, 5041. (q) Araki, K.; O'Toole, J. C.; Welch, J. T. Bioorg. Med. Chem. Lett. 1993, 3, 2457. (r) Bose, A. K.; Mathur, C.; Wagle, D. R.; Naqvi, R.; Manhas, M. S. Heterocycles 1994, 39, 491. Pyrrolizidines: (s) Cavanga, F.; Linkies, H.; Pietsch, H.; Reuschling, D. Angew. Chem., Int. Ed. Engl. 1980, 129. Pyrrolidines: (t) Bose, A. K.; Krishnan, L.; Wagle, D. R.; Manhas, M. S. Tetrahedron Lett. 1986, 27, 3955. Morfolines: (u) Wagle, D. R.; Monteleone, M. G.; Krishnan, L.; Manhas, M. S.; Bose, A. K. J. Chem. Soc., Chem. Commun. 1989, 8915.
54. For reviews of non-β-lactam products from azetidinone frameworks, see: (a) Manhas, M. S.; Wagle, D. R.; Chiang, J.; Bose, A. K. Heterocycles 1988, 27, 1755. (b) Hesse, M. In Ring Enlargement in Organic Synthesis; VCH: Weinheim, 1991; p 97. Amino acids and peptides: (c) Ojima, I. In The Organic Chemistry of β-Lactams; Georg, G. I., Ed., VCH: New York, 1992; p 197. (d) Ojima, I. Acc. Chem. Res. 1995, 28, 383. (e) Hegedus, L. S. Acc. Chem. Res. 1995, 28, 299. Aspartic acids: (f) Hanessian, S.; Sumi, K.; Vanasse, B. Synlett 1992, 23. α,β-Diamino acids: (g) Ojima, I.; Pei, Y. Tetrahedron Lett. 1990, 31, 977. Polyhydroxyamino acids: (h) Banick, B. K.; Manhas, M. S.; Bose, A. K. J. Org. Chem. 1993, 58, 307. γ-Keto α-amino acids: Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Smith, M. L.; Russel, A. T. Synlett 1993, 51. (j) Baldwin, J. E.; Adlington, R. M.; Rusell, A. T.; Smith, M. L. Tetrahedron Lett. 1995, 57, 4733. Prolines: (k) Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Vaughan, J. G. J. Chem. Soc., Chem. Commun. 1993, 1434. Baldwin, J. E.; Rudolph, M. Tetrahedron Lett. 1994, 35, 6163. Aminosugars: (m) Ha, D.-C.; Hart, D. J. Tetrahedron Lett. 1987, 28, 4489. (n) Shiozaki, M.; Ishida, N.; Sato, S. Bull. Chem. Soc. Jpn. 1989, 62, 3950. (o) Galluci, J. C.; Ha, D.-C.; Hart, D. J. Tetrahedron 1989, 45, 1283. (p) Hauser, F. M.; Ellenberger, S. R.; Rhee, R. P. J. Org. Chem. 1987, 52, 5041. (q) Araki, K.; O'Toole, J. C.; Welch, J. T. Bioorg. Med. Chem. Lett. 1993, 3, 2457. (r) Bose, A. K.; Mathur, C.; Wagle, D. R.; Naqvi, R.; Manhas, M. S. Heterocycles 1994, 39, 491. Pyrrolizidines: (s) Cavanga, F.; Linkies, H.; Pietsch, H.; Reuschling, D. Angew. Chem., Int. Ed. Engl. 1980, 129. Pyrrolidines: (t) Bose, A. K.; Krishnan, L.; Wagle, D. R.; Manhas, M. S. Tetrahedron Lett. 1986, 27, 3955. Morfolines: (u) Wagle, D. R.; Monteleone, M. G.; Krishnan, L.; Manhas, M. S.; Bose, A. K. J. Chem. Soc., Chem. Commun. 1989, 8915.
55. For reviews of non-β-lactam products from azetidinone frameworks, see: (a) Manhas, M. S.; Wagle, D. R.; Chiang, J.; Bose, A. K. Heterocycles 1988, 27, 1755. (b) Hesse, M. In Ring Enlargement in Organic Synthesis; VCH: Weinheim, 1991; p 97. Amino acids and peptides: (c) Ojima, I. In The Organic Chemistry of β-Lactams; Georg, G. I., Ed., VCH: New York, 1992; p 197. (d) Ojima, I. Acc. Chem. Res. 1995, 28, 383. (e) Hegedus, L. S. Acc. Chem. Res. 1995, 28, 299. Aspartic acids: (f) Hanessian, S.; Sumi, K.; Vanasse, B. Synlett 1992, 23. α,β-Diamino acids: (g) Ojima, I.; Pei, Y. Tetrahedron Lett. 1990, 31, 977. Polyhydroxyamino acids: (h) Banick, B. K.; Manhas, M. S.; Bose, A. K. J. Org. Chem. 1993, 58, 307. γ-Keto α-amino acids: Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Smith, M. L.; Russel, A. T. Synlett 1993, 51. (j) Baldwin, J. E.; Adlington, R. M.; Rusell, A. T.; Smith, M. L. Tetrahedron Lett. 1995, 57, 4733. Prolines: (k) Baldwin, J. E.; Adlington, R. M.; Godfrey, C. R. A.; Gollins, D. W.; Vaughan, J. G. J. Chem. Soc., Chem. Commun. 1993, 1434. Baldwin, J. E.; Rudolph, M. Tetrahedron Lett. 1994, 35, 6163. Aminosugars: (m) Ha, D.-C.; Hart, D. J. Tetrahedron Lett. 1987, 28, 4489. (n) Shiozaki, M.; Ishida, N.; Sato, S. Bull. Chem. Soc. Jpn. 1989, 62, 3950. (o) Galluci, J. C.; Ha, D.-C.; Hart, D. J. Tetrahedron 1989, 45, 1283. (p) Hauser, F. M.; Ellenberger, S. R.; Rhee, R. P. J. Org. Chem. 1987, 52, 5041. (q) Araki, K.; O'Toole, J. C.; Welch, J. T. Bioorg. Med. Chem. Lett. 1993, 3, 2457. (r) Bose, A. K.; Mathur, C.; Wagle, D. R.; Naqvi, R.; Manhas, M. S. Heterocycles 1994, 39, 491. Pyrrolizidines: (s) Cavanga, F.; Linkies, H.; Pietsch, H.; Reuschling, D. Angew. Chem., Int. Ed. Engl. 1980, 129. Pyrrolidines: (t) Bose, A. K.; Krishnan, L.; Wagle, D. R.; Manhas, M. S. Tetrahedron Lett. 1986, 27, 3955. Morfolines: (u) Wagle, D. R.; Monteleone, M. G.; Krishnan, L.; Manhas, M. S.; Bose, A. K. J. Chem. Soc., Chem. Commun. 1989, 8915.
56. For methodology to create quaternary stereogenic centers at the C(3) position, see: (a) ref 11c,d. (b) Thompson, D. K.; Suzuki, N.; Hegedus, L. S.; Satoh, Y. J. Org. Chem. 1992, 57, 1461. (c) Colson, P. J.; Hegedus, L. S. J. Org. Chem. 1993, 58, 5918.
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64. For reviews on cycloaddition of ketenes with imines, see: (a) Backes, J. In Houben-Weil Methoden der Organischen Chemie; Mueller, E., Bayer, O., Eds.; Thieme: Stuttgart, 1991; Band E16B, p 31. (b) Ghosez, L.; Marchand-Brynaert, J. In Comprehensive Organic Synthesis; Trost, B., Fleming, I., Eds.; Pergamon: Oxford, 1991; Vol. 5, p 85. (c) Thomas, R. C. In Recent Progress in the Chemical Synthesis of Antibiotics; Lukacs, G., Ohno, M., Eds.; Springer: Berlin, 1988; p 533. (d) Van der Steen, F. H.; Van Koten, G. Tetrahedron 1991, 47, 7503. (e) Georg, G. I.; Ravikumar, V. T. In The Organic Chemistry of β-Lactams; Georg, G. I., Ed.; VCH: New York, 1992; p 295.
65. For reviews on cycloaddition of ketenes with imines, see: (a) Backes, J. In Houben-Weil Methoden der Organischen Chemie; Mueller, E., Bayer, O., Eds.; Thieme: Stuttgart, 1991; Band E16B, p 31. (b) Ghosez, L.; Marchand-Brynaert, J. In Comprehensive Organic Synthesis; Trost, B., Fleming, I., Eds.; Pergamon: Oxford, 1991; Vol. 5, p 85. (c) Thomas, R. C. In Recent Progress in the Chemical Synthesis of Antibiotics; Lukacs, G., Ohno, M., Eds.; Springer: Berlin, 1988; p 533. (d) Van der Steen, F. H.; Van Koten, G. Tetrahedron 1991, 47, 7503. (e) Georg, G. I.; Ravikumar, V. T. In The Organic Chemistry of β-Lactams; Georg, G. I., Ed.; VCH: New York, 1992; p 295.
66. For reviews on cycloaddition of ketenes with imines, see: (a) Backes, J. In Houben-Weil Methoden der Organischen Chemie; Mueller, E., Bayer, O., Eds.; Thieme: Stuttgart, 1991; Band E16B, p 31. (b) Ghosez, L.; Marchand-Brynaert, J. In Comprehensive Organic Synthesis; Trost, B., Fleming, I., Eds.; Pergamon: Oxford, 1991; Vol. 5, p 85. (c) Thomas, R. C. In Recent Progress in the Chemical Synthesis of Antibiotics; Lukacs, G., Ohno, M., Eds.; Springer: Berlin, 1988; p 533. (d) Van der Steen, F. H.; Van Koten, G. Tetrahedron 1991, 47, 7503. (e) Georg, G. I.; Ravikumar, V. T. In The Organic Chemistry of β-Lactams; Georg, G. I., Ed.; VCH: New York, 1992; p 295.
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93. Owing to the easy conversion of the 4-alkoxycarbonyl group into different functional groups and/or the possibility to replace it directly by alkyl chains via decarboxylative radical conjugate addition to Michael acceptors, renders these azetidinones attractive potential building-blocks in β-lactam chemistry. See for example ref. 22 and (a) Sumi, K.; DiFabio, R.; Hanessian, S. Tetrahedron Lett. 1992, 33, 749. (b) Veiberg, G. A.; Lukevics, E. Heterocycles 1994, 38, 2309. (c) Kant, J.; Walker, D. G. In "The Organic Chemistry of β-Lactams", Georg, G. I. Ed. VCH: New York, 1992, p 121. (d) Kametani, T. Heterocycles 1982, 17, 463.
94. Owing to the easy conversion of the 4-alkoxycarbonyl group into different functional groups and/or the possibility to replace it directly by alkyl chains via decarboxylative radical conjugate addition to Michael acceptors, renders these azetidinones attractive potential building-blocks in β-lactam chemistry. See for example ref. 22 and (a) Sumi, K.; DiFabio, R.; Hanessian, S. Tetrahedron Lett. 1992, 33, 749. (b) Veiberg, G. A.; Lukevics, E. Heterocycles 1994, 38, 2309. (c) Kant, J.; Walker, D. G. In "The Organic Chemistry of β-Lactams", Georg, G. I. Ed. VCH: New York, 1992, p 121. (d) Kametani, T. Heterocycles 1982, 17, 463.
95. Owing to the easy conversion of the 4-alkoxycarbonyl group into different functional groups and/or the possibility to replace it directly by alkyl chains via decarboxylative radical conjugate addition to Michael acceptors, renders these azetidinones attractive potential building-blocks in β-lactam chemistry. See for example ref. 22 and (a) Sumi, K.; DiFabio, R.; Hanessian, S. Tetrahedron Lett. 1992, 33, 749. (b) Veiberg, G. A.; Lukevics, E. Heterocycles 1994, 38, 2309. (c) Kant, J.; Walker, D. G. In "The Organic Chemistry of β-Lactams", Georg, G. I. Ed. VCH: New York, 1992, p 121. (d) Kametani, T. Heterocycles 1982, 17, 463.
96. Owing to the easy conversion of the 4-alkoxycarbonyl group into different functional groups and/or the possibility to replace it directly by alkyl chains via decarboxylative radical conjugate addition to Michael acceptors, renders these azetidinones attractive potential building-blocks in β-lactam chemistry. See for example ref. 22 and (a) Sumi, K.; DiFabio, R.; Hanessian, S. Tetrahedron Lett. 1992, 33, 749. (b) Veiberg, G. A.; Lukevics, E. Heterocycles 1994, 38, 2309. (c) Kant, J.; Walker, D. G. In "The Organic Chemistry of β-Lactams", Georg, G. I. Ed. VCH: New York, 1992, p 121. (d) Kametani, T. Heterocycles 1982, 17, 463.
97. For the preparation of homochiral β-silylalkanoyl chlorides, see: Palomo, C.; Aizpurua, J. M.; Iturburu, M.; Urchegui, R. J. Org. Chem. 1994, 59, 240, and references therein.
98. (a) Evans, D. A.; Sjögren, E. B. Tetrahedron Lett. 1985, 26, 3783.
99. (b) Evans, D. A.; Sjögren, E. B. Ibid. 1985, 26, 3788.
100. Hegedus, L. S.; Imiwinkelried, R.; Alarid-Sargent, M.; Dvorak, D.; Satoh, Y. J. Am. Chem. Soc. 1990, 112, 1109.
101. (a) Cossio, F. P.; Ugalde, J. M.; Lopez, X.; Lecea, B.; Palomo, C. J. Am. Chem. Soc. 1993, 115, 995.
102. (b) Sordo, J. A.; Gonzalez, J.; Sordo, T. L. J. Am. Chem. Soc. 1992, 114, 6249.
103. (c) Arrieta, A.; Lecea, B.; Ugalde, J. M. J. Am. Chem. Soc. 1994, 116, 2085.
104. Palomo, C.; Aizpurua, J. M.; Legido, M.; Galarza, R.; Deya, P. M.; Dunogues, J.; Picard, J. P.; Ricci, A.; Seconi, G. Angew. Chem., Int. Ed. Engl. 1996, 11, 1239.
105. After completion of this work, a paper dealing with the synthesis of 4,4-disubstituted β-lactams via hydroxamate methodology has been appeared. See: Ageno, G.; Banfi, L.; Cascio, G.; Guanti, G.; Manghisi, E.; Riva, R.; Rocca, V. Tetrahedron 1995, 51, 8121.
106. Review: Lambert, J. B. Tetrahedron 1990, 46, 2677.
107. 3, HMPA-THF) of either cyanotrimethylsilane or N,N-dimethylcyanamide. For details, see: (a) Picard, J. P.; Grelier, S.; Constantieux, T.; Dunogues, J.; Aizpurua, J. M.; Palomo, C.; Pétraud, M.; Barbe, B.; Lunazzi, L.; Leger, J. M. Organometallics 1993, 12, 1378. (b) Grelier, S.; Constantieux, T.; Deffieux, D.; Bordeau, M.; Dunogues, J.; Picard, J. P.; Palomo, C.; Aizpurua, J. M. Organometallics 1994, 13, 3711.
108. 3, HMPA-THF) of either cyanotrimethylsilane or N,N-dimethylcyanamide. For details, see: (a) Picard, J. P.; Grelier, S.; Constantieux, T.; Dunogues, J.; Aizpurua, J. M.; Palomo, C.; Pétraud, M.; Barbe, B.; Lunazzi, L.; Leger, J. M. Organometallics 1993, 12, 1378. (b) Grelier, S.; Constantieux, T.; Deffieux, D.; Bordeau, M.; Dunogues, J.; Picard, J. P.; Palomo, C.; Aizpurua, J. M. Organometallics 1994, 13, 3711.
109. Lasarte, J.; Palomo, C.; Picard, J. P.; Dunogues, J.; Aizpurua, J. M. J. Chem. Soc., Chem. Commun. 1989, 72.
110. Palomo, C.; Aizpurua, J. M.; Legido, M.; Picard, J. P.; Dunogues, J.; Constantieux, T. Tetrahedron Lett. 1992, 33, 3903.
111. Palomo, C.; Aizpurua, J. M.; García, J. M.; Legido, M. J. Chem. Soc., Chem. Commun. 1991, 524.
112. (a) Palomo, C.; Aizpurua, J. M.; García, J. M.;Ganboa, I.; Cossio, F. P.; Lecea, B.; Lopez, C. J. Org. Chem. 1980, 55, 2498.
113. (b) Palomo, C.; Aizpurua, J. M.; Garcia, J. M.; Picard, J. P.; Dunogues, J. Tetrahedron Lett. 1990, 31, 1921.
114. These ketimines were prepared by mixing an excess of the: corresponding ketone (20 mL) and C,C-bis(trimethylsilyl)methylamine (10 mmol) and stirring overnight either at room temperature (for 34a, 34b, and 34d) or at reflux temperature for (34c). On completion, the: excess of ketone was evaporated, and the imines were purified by reduced pressure distillation.
115. The bis(trimethylsilyl)methyl moiety was first removed using the following three-step sequence according to the procedure given in ref 35. Chemical equation presented.
116. This method was inspired in the work by Mariano: Zhang, X. M.; Jung, Y. S.; Mariano, P. S.; Fox, M. A.; Martin, P. S.; Merkert, J. Tetrahedron Lett. 1993, 34, 5239.
117. The acylation of the intermediate 3-amino β-lactam with Cbz-Cl produced a side product which was not identified. On the other hand, removal of the oxazolidinone ring after deprotection of the N-substituent caused complete destruction of the corresponding β-lactam.
118. For N-deformylation methods, see: Georg, G. I.; He, P.; Kant, J.; Wu, Z. J. J. Org. Chem. 1993, 58, 5771.
119. For a more detailed experimental information on this subject, see: Palomo, C.; Aizpurua, J. M.; Galarza, R.; Mielgo, A. J. Chem. Soc., Chem. Commun. 1996, 633.
120. For a recent study documenting this aspect, see: Ruhland, B.; Bhandari, A.; Gordon, E. M.; Gallop, M. A. J. Am. Chem. Soc. 1996, 118, 253.
121. The authors have deposited the atomic coordinates for this structure with the Cambridge Crystallographic Data Centre. The coordinates can be obtained, on request, from the Director, Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge, CB2 1EZ, UK.