Rigid dipeptide surrogates: Syntheses of enantiopure quinolizidinone and pyrroloazepinone amino acids from a common diaminodicarboxylate precursor

Journal of Organic Chemistry

Volumn 65, Issue 7, 2000, Pages 2163-2171

  Gosselin, Francis ^a   Lubell, William D ^a  

^a UNIVERSITÉ DE MONTRÉAL   (Canada)

Author keywords

[No Author keywords available]

Indexed keywords

AMINO ACID DERIVATIVE; AZEPINE DERIVATIVE; DICARBOXYLIC ACID DERIVATIVE; MESYLIC ACID; PHOSPHONIC ACID DERIVATIVE; PROLINE DERIVATIVE; PYROGLUTAMIC ACID; QUINOLIZIDINE DERIVATIVE;

AMINO ACID SYNTHESIS; ARTICLE; CHEMICAL REACTION; CHEMICAL STRUCTURE; CYCLIZATION; HYDROGENATION; PROTEIN CONFORMATION; STEREOISOMERISM;

AMINO ACIDS; AMINO ACIDS, DICARBOXYLIC; AZEPINES; CRYSTALLOGRAPHY, X-RAY; DIPEPTIDES; MOLECULAR CONFORMATION; PYRROLES; QUINOLONES; STEREOISOMERISM;

EID: 0034616373     PISSN: 00223263     EISSN: None     Source Type: Journal    
DOI: 10.1021/jo991766o     Document Type: Article

References (70)

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59. In our hands, onium salt based coupling reagents were superior to all other methods. Earlier attempts provided lower yields of the desired seven-membered lactams using (a) catecholborane: Collum, D. B.; Chen, S.-C.; Ganem, B. J. Org. Chem. 1978, 43, 439, as well as peptide coupling reagents such as the following: (b) Carbodiimides: Sheehan, J. C.; Hess, G. P. J. Am. Chem. Soc. 1955, 77, 1067. (c) (1-Azabenzotriazolyloxy)tris(dimethylamino)phosphonium hexafluorophosphate (BOP): Castro, B.; Dormoy, J. R.; Evin, G.; Selve, C. Tetrahedron Lett. 1975, 14, 1219. (d) Bis(2-oxo-3-oxazolidinyl)phosphinic chloride (BOP-Cl): Tung, R. D.; Rich, D. H. J. Am. Chem. Soc. 1985, 107, 4342. (e) Diphenylphosphoryl azide (DPPA): see ref 20. For a discussion on the use of peptide coupling agents in synthesis, see (f) Humphrey, J. M.; Chamberlin, A. R. Chem. Rev. 1997, 97, 2243.
60. In our hands, onium salt based coupling reagents were superior to all other methods. Earlier attempts provided lower yields of the desired seven-membered lactams using (a) catecholborane: Collum, D. B.; Chen, S.-C.; Ganem, B. J. Org. Chem. 1978, 43, 439, as well as peptide coupling reagents such as the following: (b) Carbodiimides: Sheehan, J. C.; Hess, G. P. J. Am. Chem. Soc. 1955, 77, 1067. (c) (1-Azabenzotriazolyloxy)tris(dimethylamino)phosphonium hexafluorophosphate (BOP): Castro, B.; Dormoy, J. R.; Evin, G.; Selve, C. Tetrahedron Lett. 1975, 14, 1219. (d) Bis(2-oxo-3-oxazolidinyl)phosphinic chloride (BOP-Cl): Tung, R. D.; Rich, D. H. J. Am. Chem. Soc. 1985, 107, 4342. (e) Diphenylphosphoryl azide (DPPA): see ref 20. For a discussion on the use of peptide coupling agents in synthesis, see (f) Humphrey, J. M.; Chamberlin, A. R. Chem. Rev. 1997, 97, 2243.
61. In our hands, onium salt based coupling reagents were superior to all other methods. Earlier attempts provided lower yields of the desired seven-membered lactams using (a) catecholborane: Collum, D. B.; Chen, S.-C.; Ganem, B. J. Org. Chem. 1978, 43, 439, as well as peptide coupling reagents such as the following: (b) Carbodiimides: Sheehan, J. C.; Hess, G. P. J. Am. Chem. Soc. 1955, 77, 1067. (c) (1-Azabenzotriazolyloxy)tris(dimethylamino)phosphonium hexafluorophosphate (BOP): Castro, B.; Dormoy, J. R.; Evin, G.; Selve, C. Tetrahedron Lett. 1975, 14, 1219. (d) Bis(2-oxo-3-oxazolidinyl)phosphinic chloride (BOP-Cl): Tung, R. D.; Rich, D. H. J. Am. Chem. Soc. 1985, 107, 4342. (e) Diphenylphosphoryl azide (DPPA): see ref 20. For a discussion on the use of peptide coupling agents in synthesis, see (f) Humphrey, J. M.; Chamberlin, A. R. Chem. Rev. 1997, 97, 2243.
62. In our hands, onium salt based coupling reagents were superior to all other methods. Earlier attempts provided lower yields of the desired seven-membered lactams using (a) catecholborane: Collum, D. B.; Chen, S.-C.; Ganem, B. J. Org. Chem. 1978, 43, 439, as well as peptide coupling reagents such as the following: (b) Carbodiimides: Sheehan, J. C.; Hess, G. P. J. Am. Chem. Soc. 1955, 77, 1067. (c) (1-Azabenzotriazolyloxy)tris(dimethylamino)phosphonium hexafluorophosphate (BOP): Castro, B.; Dormoy, J. R.; Evin, G.; Selve, C. Tetrahedron Lett. 1975, 14, 1219. (d) Bis(2-oxo-3-oxazolidinyl)phosphinic chloride (BOP-Cl): Tung, R. D.; Rich, D. H. J. Am. Chem. Soc. 1985, 107, 4342. (e) Diphenylphosphoryl azide (DPPA): see ref 20. For a discussion on the use of peptide coupling agents in synthesis, see (f) Humphrey, J. M.; Chamberlin, A. R. Chem. Rev. 1997, 97, 2243.
63. In our hands, onium salt based coupling reagents were superior to all other methods. Earlier attempts provided lower yields of the desired seven-membered lactams using (a) catecholborane: Collum, D. B.; Chen, S.-C.; Ganem, B. J. Org. Chem. 1978, 43, 439, as well as peptide coupling reagents such as the following: (b) Carbodiimides: Sheehan, J. C.; Hess, G. P. J. Am. Chem. Soc. 1955, 77, 1067. (c) (1-Azabenzotriazolyloxy)tris(dimethylamino)phosphonium hexafluorophosphate (BOP): Castro, B.; Dormoy, J. R.; Evin, G.; Selve, C. Tetrahedron Lett. 1975, 14, 1219. (d) Bis(2-oxo-3-oxazolidinyl)phosphinic chloride (BOP-Cl): Tung, R. D.; Rich, D. H. J. Am. Chem. Soc. 1985, 107, 4342. (e) Diphenylphosphoryl azide (DPPA): see ref 20. For a discussion on the use of peptide coupling agents in synthesis, see (f) Humphrey, J. M.; Chamberlin, A. R. Chem. Rev. 1997, 97, 2243.
64. In comparison, formation of the seven-membered lactam by iminium ion cyclization and by radical-mediated cyclization went respectively in 79% and 42-61% yields, as discussed in refs 7 and 11.
65. (a) Dangles, O.; Guibé, F.; Balavoine, G.; Lavielle, S.; Marquet, A. J. Org. Chem. 1987, 52, 4984.
66. (b) Loffet, A.; Zhang, H. X. Int. J. Pept. Protein Res. 1993, 42, 346.
67. 2 = 0.12 for all data; GOF = 1.065. The author has deposited the atomic coordinates for the structure of 20 with the Cambridge Crystallographic Data Center. The coordinates can be obtained, on request, from the Cambridge Crystallographic Data Center, 12 Union Road, Cambridge, CB2 1EZ, U.K.
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70. By comparison, the iminium ion cyclization route required 11 steps and provided N-phthalyl pyrroloazepinone methyl ester in 23% overall yield from the more advanced intermediates N-phthalyl-L-allylglycine and N-phthalyl γ-benzyl glutamate. The radical cyclization based strategy took seven steps and provided N-acetyl pyrroloazepinone tert-butyl ester in 16-24% overall yield from the advanced intermediate (2S,5S)-diethyl N-benzylpyrrolidine 2,5-dicarboxylate.