Synthesis and properties of oligonucleotides having a phosphorus chiral center by incorporation of conformationally rigid 5'-cyclouridylic acid derivatives

Journal of Organic Chemistry

Volumn 65, Issue 20, 2000, Pages 6515-6524

  Sekine, Mitsuo ^a   Kurasawa, Osamu ^a   Shohda, Koh Ichiroh ^a   Seio, Kohji ^a   Wada, Takeshi ^a  

^a TOKYO INSTITUTE OF TECHNOLOGY   (Japan)

Author keywords

[No Author keywords available]

Indexed keywords

CYCLIC UMP; DNA; OLIGONUCLEOTIDE; RNA; URIDINE DERIVATIVE;

ARTICLE; CHEMICAL STRUCTURE; CHIRALITY; DIASTEREOISOMER; NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY; STRUCTURE ANALYSIS; SYNTHESIS; THREE DIMENSIONAL IMAGING;

CIRCULAR DICHROISM; DNA; MAGNETIC RESONANCE SPECTROSCOPY; MODELS, MOLECULAR; NUCLEIC ACID CONFORMATION; NUCLEOTIDES, CYCLIC; OLIGONUCLEOTIDES; PHOSPHORUS; RNA; STEREOISOMERISM; URIDINE MONOPHOSPHATE;

EID: 0034613123     PISSN: 00223263     EISSN: None     Source Type: Journal    
DOI: 10.1021/jo0002588     Document Type: Article

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34. In connection with the present study, there have been reported conformationally locked nucleosides: (a) Tarköy, M.; Bolli, M.; Schweizer, B.: Leumann, C. Helv. Chim. Acta 1993, 76, 481-510. (b) Egli, M.; Lubini, P.; Bolli, M.; Dobler, M.; Leumann, C. J. Am. Chem. Soc. 1993, 115, 5855-5856. (c) Tarköy, M.; Leumann, C. Angew. Chem., Int. Ed. Engl. 1993, 32, 1432-1434. (d) Tarköy, M.; Bolli, M.; Leumann, C. Helv. Chim. Acta 1994, 77, 716-744. (e) Bolli, M.; Lubini, P.; Leumann, C. Helv. Chim. Acta 1995, 78, 2077-2096. (f) Litten, C. J.; Epple, C.; Leumann, C. J.; Bioorg. Med. Chem. Lett. 1995, 5, 1231- 1234. (g) Litten, J. C.; Leumann, C. Helv. Chim. Acta 1996, 79, 1129- 1146. (h) Jones, R. J.; Swaminathan, S.; Milligan, J. F.; Wadwani, S.; Froehler, B. C.; Matteucci, M. D. J. Am. Chem. Soc. 1993, 115, 9816- 9817. (i) Zou, R.; Matteucci, M. D. Tetrahedron Lett. 1996, 37, 941- 944. (j) Altmann, K.-H.; Kesselring, R.; Francotte, E.; Rihs, G. Tetrahedron Lett. 1994, 35, 2331-2334. (k) Altmann, K.-H.; Imwinkelried, R.; Kesselring, R.; Rihs, G. Tetrahedron Lett. 1994, 35, 7625- 7628. (l) Herdewijn, P. Liebigs Ann. 1996, 1337-1348. (m) Egli, M. Angew. Chem., Int. Ed. Engl. 1996, 35, 1894-1909. (n) Ezzitouni, A.; Russ, P.; Marquez, V. E. J. Org. Chem. 1997, 62, 4870-4873. (o) Obika, S.; Nanbu, D.; Hari, Y.; Morio, K.; In, Y.; Ishida, T.; Imanishi, T. Tetrahedron Lett. 1997, 38, 8735-8738. (p) Obika, S.; Morio, K.; Nanbu, D.; Imanishi, T. Chem. Commun. 1997, 1643-1644. (q) Obika, S.; Nanbu, D.; Hari, Y.; Andoh, J.; Morio, K.; Doi, T.; Imanishi, T. Tetrahedron Lett. 1998, 39, 5401-5404. (r) Singh, S. K.; Nielsen, P.; Koshkin, A. A.; Wengel, J. Chem. Commun. 1998, 455-456. (s) Koshkin, A. A.; Singh, S. K.; Nielsen, P.; Rajwanshi, V. K.; Kumar, R.; Meldgaard, M.; Olsen, C. E.; Wengel, J. Tetrahedron 1998, 54, 3607-3630. (t) Christensen, N. K.; Petersen, M.; Nielsen, P.; Jacobsen, J. P.; Olsen, C. E.; Wengel, J. J. Am. Chem. Soc. 1998, 120, 5458- 5463. (u) Wang, G.; Gunic, E.; Girardet, J.-L.; Stoisavljevic, V. Bioorg. Med. Chem. Lett. 1999, 9, 1147-1150.
35. In connection with the present study, there have been reported conformationally locked nucleosides: (a) Tarköy, M.; Bolli, M.; Schweizer, B.: Leumann, C. Helv. Chim. Acta 1993, 76, 481-510. (b) Egli, M.; Lubini, P.; Bolli, M.; Dobler, M.; Leumann, C. J. Am. Chem. Soc. 1993, 115, 5855-5856. (c) Tarköy, M.; Leumann, C. Angew. Chem., Int. Ed. Engl. 1993, 32, 1432-1434. (d) Tarköy, M.; Bolli, M.; Leumann, C. Helv. Chim. Acta 1994, 77, 716-744. (e) Bolli, M.; Lubini, P.; Leumann, C. Helv. Chim. Acta 1995, 78, 2077-2096. (f) Litten, C. J.; Epple, C.; Leumann, C. J.; Bioorg. Med. Chem. Lett. 1995, 5, 1231- 1234. (g) Litten, J. C.; Leumann, C. Helv. Chim. Acta 1996, 79, 1129- 1146. (h) Jones, R. J.; Swaminathan, S.; Milligan, J. F.; Wadwani, S.; Froehler, B. C.; Matteucci, M. D. J. Am. Chem. Soc. 1993, 115, 9816- 9817. (i) Zou, R.; Matteucci, M. D. Tetrahedron Lett. 1996, 37, 941- 944. (j) Altmann, K.-H.; Kesselring, R.; Francotte, E.; Rihs, G. Tetrahedron Lett. 1994, 35, 2331-2334. (k) Altmann, K.-H.; Imwinkelried, R.; Kesselring, R.; Rihs, G. Tetrahedron Lett. 1994, 35, 7625- 7628. (l) Herdewijn, P. Liebigs Ann. 1996, 1337-1348. (m) Egli, M. Angew. Chem., Int. Ed. Engl. 1996, 35, 1894-1909. (n) Ezzitouni, A.; Russ, P.; Marquez, V. E. J. Org. Chem. 1997, 62, 4870-4873. (o) Obika, S.; Nanbu, D.; Hari, Y.; Morio, K.; In, Y.; Ishida, T.; Imanishi, T. Tetrahedron Lett. 1997, 38, 8735-8738. (p) Obika, S.; Morio, K.; Nanbu, D.; Imanishi, T. Chem. Commun. 1997, 1643-1644. (q) Obika, S.; Nanbu, D.; Hari, Y.; Andoh, J.; Morio, K.; Doi, T.; Imanishi, T. Tetrahedron Lett. 1998, 39, 5401-5404. (r) Singh, S. K.; Nielsen, P.; Koshkin, A. A.; Wengel, J. Chem. Commun. 1998, 455-456. (s) Koshkin, A. A.; Singh, S. K.; Nielsen, P.; Rajwanshi, V. K.; Kumar, R.; Meldgaard, M.; Olsen, C. E.; Wengel, J. Tetrahedron 1998, 54, 3607-3630. (t) Christensen, N. K.; Petersen, M.; Nielsen, P.; Jacobsen, J. P.; Olsen, C. E.; Wengel, J. J. Am. Chem. Soc. 1998, 120, 5458- 5463. (u) Wang, G.; Gunic, E.; Girardet, J.-L.; Stoisavljevic, V. Bioorg. Med. Chem. Lett. 1999, 9, 1147-1150.
36. In connection with the present study, there have been reported conformationally locked nucleosides: (a) Tarköy, M.; Bolli, M.; Schweizer, B.: Leumann, C. Helv. Chim. Acta 1993, 76, 481-510. (b) Egli, M.; Lubini, P.; Bolli, M.; Dobler, M.; Leumann, C. J. Am. Chem. Soc. 1993, 115, 5855-5856. (c) Tarköy, M.; Leumann, C. Angew. Chem., Int. Ed. Engl. 1993, 32, 1432-1434. (d) Tarköy, M.; Bolli, M.; Leumann, C. Helv. Chim. Acta 1994, 77, 716-744. (e) Bolli, M.; Lubini, P.; Leumann, C. Helv. Chim. Acta 1995, 78, 2077-2096. (f) Litten, C. J.; Epple, C.; Leumann, C. J.; Bioorg. Med. Chem. Lett. 1995, 5, 1231- 1234. (g) Litten, J. C.; Leumann, C. Helv. Chim. Acta 1996, 79, 1129- 1146. (h) Jones, R. J.; Swaminathan, S.; Milligan, J. F.; Wadwani, S.; Froehler, B. C.; Matteucci, M. D. J. Am. Chem. Soc. 1993, 115, 9816- 9817. (i) Zou, R.; Matteucci, M. D. Tetrahedron Lett. 1996, 37, 941- 944. (j) Altmann, K.-H.; Kesselring, R.; Francotte, E.; Rihs, G. Tetrahedron Lett. 1994, 35, 2331-2334. (k) Altmann, K.-H.; Imwinkelried, R.; Kesselring, R.; Rihs, G. Tetrahedron Lett. 1994, 35, 7625- 7628. (l) Herdewijn, P. Liebigs Ann. 1996, 1337-1348. (m) Egli, M. Angew. Chem., Int. Ed. Engl. 1996, 35, 1894-1909. (n) Ezzitouni, A.; Russ, P.; Marquez, V. E. J. Org. Chem. 1997, 62, 4870-4873. (o) Obika, S.; Nanbu, D.; Hari, Y.; Morio, K.; In, Y.; Ishida, T.; Imanishi, T. Tetrahedron Lett. 1997, 38, 8735-8738. (p) Obika, S.; Morio, K.; Nanbu, D.; Imanishi, T. Chem. Commun. 1997, 1643-1644. (q) Obika, S.; Nanbu, D.; Hari, Y.; Andoh, J.; Morio, K.; Doi, T.; Imanishi, T. Tetrahedron Lett. 1998, 39, 5401-5404. (r) Singh, S. K.; Nielsen, P.; Koshkin, A. A.; Wengel, J. Chem. Commun. 1998, 455-456. (s) Koshkin, A. A.; Singh, S. K.; Nielsen, P.; Rajwanshi, V. K.; Kumar, R.; Meldgaard, M.; Olsen, C. E.; Wengel, J. Tetrahedron 1998, 54, 3607-3630. (t) Christensen, N. K.; Petersen, M.; Nielsen, P.; Jacobsen, J. P.; Olsen, C. E.; Wengel, J. J. Am. Chem. Soc. 1998, 120, 5458- 5463. (u) Wang, G.; Gunic, E.; Girardet, J.-L.; Stoisavljevic, V. Bioorg. Med. Chem. Lett. 1999, 9, 1147-1150.
37. In connection with the present study, there have been reported conformationally locked nucleosides: (a) Tarköy, M.; Bolli, M.; Schweizer, B.: Leumann, C. Helv. Chim. Acta 1993, 76, 481-510. (b) Egli, M.; Lubini, P.; Bolli, M.; Dobler, M.; Leumann, C. J. Am. Chem. Soc. 1993, 115, 5855-5856. (c) Tarköy, M.; Leumann, C. Angew. Chem., Int. Ed. Engl. 1993, 32, 1432-1434. (d) Tarköy, M.; Bolli, M.; Leumann, C. Helv. Chim. Acta 1994, 77, 716-744. (e) Bolli, M.; Lubini, P.; Leumann, C. Helv. Chim. Acta 1995, 78, 2077-2096. (f) Litten, C. J.; Epple, C.; Leumann, C. J.; Bioorg. Med. Chem. Lett. 1995, 5, 1231- 1234. (g) Litten, J. C.; Leumann, C. Helv. Chim. Acta 1996, 79, 1129- 1146. (h) Jones, R. J.; Swaminathan, S.; Milligan, J. F.; Wadwani, S.; Froehler, B. C.; Matteucci, M. D. J. Am. Chem. Soc. 1993, 115, 9816- 9817. (i) Zou, R.; Matteucci, M. D. Tetrahedron Lett. 1996, 37, 941- 944. (j) Altmann, K.-H.; Kesselring, R.; Francotte, E.; Rihs, G. Tetrahedron Lett. 1994, 35, 2331-2334. (k) Altmann, K.-H.; Imwinkelried, R.; Kesselring, R.; Rihs, G. Tetrahedron Lett. 1994, 35, 7625- 7628. (l) Herdewijn, P. Liebigs Ann. 1996, 1337-1348. (m) Egli, M. Angew. Chem., Int. Ed. Engl. 1996, 35, 1894-1909. (n) Ezzitouni, A.; Russ, P.; Marquez, V. E. J. Org. Chem. 1997, 62, 4870-4873. (o) Obika, S.; Nanbu, D.; Hari, Y.; Morio, K.; In, Y.; Ishida, T.; Imanishi, T. Tetrahedron Lett. 1997, 38, 8735-8738. (p) Obika, S.; Morio, K.; Nanbu, D.; Imanishi, T. Chem. Commun. 1997, 1643-1644. (q) Obika, S.; Nanbu, D.; Hari, Y.; Andoh, J.; Morio, K.; Doi, T.; Imanishi, T. Tetrahedron Lett. 1998, 39, 5401-5404. (r) Singh, S. K.; Nielsen, P.; Koshkin, A. A.; Wengel, J. Chem. Commun. 1998, 455-456. (s) Koshkin, A. A.; Singh, S. K.; Nielsen, P.; Rajwanshi, V. K.; Kumar, R.; Meldgaard, M.; Olsen, C. E.; Wengel, J. Tetrahedron 1998, 54, 3607-3630. (t) Christensen, N. K.; Petersen, M.; Nielsen, P.; Jacobsen, J. P.; Olsen, C. E.; Wengel, J. J. Am. Chem. Soc. 1998, 120, 5458- 5463. (u) Wang, G.; Gunic, E.; Girardet, J.-L.; Stoisavljevic, V. Bioorg. Med. Chem. Lett. 1999, 9, 1147-1150.
38. In connection with the present study, there have been reported conformationally locked nucleosides: (a) Tarköy, M.; Bolli, M.; Schweizer, B.: Leumann, C. Helv. Chim. Acta 1993, 76, 481-510. (b) Egli, M.; Lubini, P.; Bolli, M.; Dobler, M.; Leumann, C. J. Am. Chem. Soc. 1993, 115, 5855-5856. (c) Tarköy, M.; Leumann, C. Angew. Chem., Int. Ed. Engl. 1993, 32, 1432-1434. (d) Tarköy, M.; Bolli, M.; Leumann, C. Helv. Chim. Acta 1994, 77, 716-744. (e) Bolli, M.; Lubini, P.; Leumann, C. Helv. Chim. Acta 1995, 78, 2077-2096. (f) Litten, C. J.; Epple, C.; Leumann, C. J.; Bioorg. Med. Chem. Lett. 1995, 5, 1231-1234. (g) Litten, J. C.; Leumann, C. Helv. Chim. Acta 1996, 79, 1129- 1146. (h) Jones, R. J.; Swaminathan, S.; Milligan, J. F.; Wadwani, S.; Froehler, B. C.; Matteucci, M. D. J. Am. Chem. Soc. 1993, 115, 9816- 9817. (i) Zou, R.; Matteucci, M. D. Tetrahedron Lett. 1996, 37, 941- 944. (j) Altmann, K.-H.; Kesselring, R.; Francotte, E.; Rihs, G. Tetrahedron Lett. 1994, 35, 2331-2334. (k) Altmann, K.-H.; Imwinkelried, R.; Kesselring, R.; Rihs, G. Tetrahedron Lett. 1994, 35, 7625- 7628. (l) Herdewijn, P. Liebigs Ann. 1996, 1337-1348. (m) Egli, M. Angew. Chem., Int. Ed. Engl. 1996, 35, 1894-1909. (n) Ezzitouni, A.; Russ, P.; Marquez, V. E. J. Org. Chem. 1997, 62, 4870-4873. (o) Obika, S.; Nanbu, D.; Hari, Y.; Morio, K.; In, Y.; Ishida, T.; Imanishi, T. Tetrahedron Lett. 1997, 38, 8735-8738. (p) Obika, S.; Morio, K.; Nanbu, D.; Imanishi, T. Chem. Commun. 1997, 1643-1644. (q) Obika, S.; Nanbu, D.; Hari, Y.; Andoh, J.; Morio, K.; Doi, T.; Imanishi, T. Tetrahedron Lett. 1998, 39, 5401-5404. (r) Singh, S. K.; Nielsen, P.; Koshkin, A. A.; Wengel, J. Chem. Commun. 1998, 455-456. (s) Koshkin, A. A.; Singh, S. K.; Nielsen, P.; Rajwanshi, V. K.; Kumar, R.; Meldgaard, M.; Olsen, C. E.; Wengel, J. Tetrahedron 1998, 54, 3607-3630. (t) Christensen, N. K.; Petersen, M.; Nielsen, P.; Jacobsen, J. P.; Olsen, C. E.; Wengel, J. J. Am. Chem. Soc. 1998, 120, 5458- 5463. (u) Wang, G.; Gunic, E.; Girardet, J.-L.; Stoisavljevic, V. Bioorg. Med. Chem. Lett. 1999, 9, 1147-1150.
39. In connection with the present study, there have been reported conformationally locked nucleosides: (a) Tarköy, M.; Bolli, M.; Schweizer, B.: Leumann, C. Helv. Chim. Acta 1993, 76, 481-510. (b) Egli, M.; Lubini, P.; Bolli, M.; Dobler, M.; Leumann, C. J. Am. Chem. Soc. 1993, 115, 5855-5856. (c) Tarköy, M.; Leumann, C. Angew. Chem., Int. Ed. Engl. 1993, 32, 1432-1434. (d) Tarköy, M.; Bolli, M.; Leumann, C. Helv. Chim. Acta 1994, 77, 716-744. (e) Bolli, M.; Lubini, P.; Leumann, C. Helv. Chim. Acta 1995, 78, 2077-2096. (f) Litten, C. J.; Epple, C.; Leumann, C. J.; Bioorg. Med. Chem. Lett. 1995, 5, 1231- 1234. (g) Litten, J. C.; Leumann, C. Helv. Chim. Acta 1996, 79, 1129-1146. (h) Jones, R. J.; Swaminathan, S.; Milligan, J. F.; Wadwani, S.; Froehler, B. C.; Matteucci, M. D. J. Am. Chem. Soc. 1993, 115, 9816- 9817. (i) Zou, R.; Matteucci, M. D. Tetrahedron Lett. 1996, 37, 941- 944. (j) Altmann, K.-H.; Kesselring, R.; Francotte, E.; Rihs, G. Tetrahedron Lett. 1994, 35, 2331-2334. (k) Altmann, K.-H.; Imwinkelried, R.; Kesselring, R.; Rihs, G. Tetrahedron Lett. 1994, 35, 7625- 7628. (l) Herdewijn, P. Liebigs Ann. 1996, 1337-1348. (m) Egli, M. Angew. Chem., Int. Ed. Engl. 1996, 35, 1894-1909. (n) Ezzitouni, A.; Russ, P.; Marquez, V. E. J. Org. Chem. 1997, 62, 4870-4873. (o) Obika, S.; Nanbu, D.; Hari, Y.; Morio, K.; In, Y.; Ishida, T.; Imanishi, T. Tetrahedron Lett. 1997, 38, 8735-8738. (p) Obika, S.; Morio, K.; Nanbu, D.; Imanishi, T. Chem. Commun. 1997, 1643-1644. (q) Obika, S.; Nanbu, D.; Hari, Y.; Andoh, J.; Morio, K.; Doi, T.; Imanishi, T. Tetrahedron Lett. 1998, 39, 5401-5404. (r) Singh, S. K.; Nielsen, P.; Koshkin, A. A.; Wengel, J. Chem. Commun. 1998, 455-456. (s) Koshkin, A. A.; Singh, S. K.; Nielsen, P.; Rajwanshi, V. K.; Kumar, R.; Meldgaard, M.; Olsen, C. E.; Wengel, J. Tetrahedron 1998, 54, 3607-3630. (t) Christensen, N. K.; Petersen, M.; Nielsen, P.; Jacobsen, J. P.; Olsen, C. E.; Wengel, J. J. Am. Chem. Soc. 1998, 120, 5458- 5463. (u) Wang, G.; Gunic, E.; Girardet, J.-L.; Stoisavljevic, V. Bioorg. Med. Chem. Lett. 1999, 9, 1147-1150.
40. In connection with the present study, there have been reported conformationally locked nucleosides: (a) Tarköy, M.; Bolli, M.; Schweizer, B.: Leumann, C. Helv. Chim. Acta 1993, 76, 481-510. (b) Egli, M.; Lubini, P.; Bolli, M.; Dobler, M.; Leumann, C. J. Am. Chem. Soc. 1993, 115, 5855-5856. (c) Tarköy, M.; Leumann, C. Angew. Chem., Int. Ed. Engl. 1993, 32, 1432-1434. (d) Tarköy, M.; Bolli, M.; Leumann, C. Helv. Chim. Acta 1994, 77, 716-744. (e) Bolli, M.; Lubini, P.; Leumann, C. Helv. Chim. Acta 1995, 78, 2077-2096. (f) Litten, C. J.; Epple, C.; Leumann, C. J.; Bioorg. Med. Chem. Lett. 1995, 5, 1231- 1234. (g) Litten, J. C.; Leumann, C. Helv. Chim. Acta 1996, 79, 1129- 1146. (h) Jones, R. J.; Swaminathan, S.; Milligan, J. F.; Wadwani, S.; Froehler, B. C.; Matteucci, M. D. J. Am. Chem. Soc. 1993, 115, 9816-9817. (i) Zou, R.; Matteucci, M. D. Tetrahedron Lett. 1996, 37, 941- 944. (j) Altmann, K.-H.; Kesselring, R.; Francotte, E.; Rihs, G. Tetrahedron Lett. 1994, 35, 2331-2334. (k) Altmann, K.-H.; Imwinkelried, R.; Kesselring, R.; Rihs, G. Tetrahedron Lett. 1994, 35, 7625- 7628. (l) Herdewijn, P. Liebigs Ann. 1996, 1337-1348. (m) Egli, M. Angew. Chem., Int. Ed. Engl. 1996, 35, 1894-1909. (n) Ezzitouni, A.; Russ, P.; Marquez, V. E. J. Org. Chem. 1997, 62, 4870-4873. (o) Obika, S.; Nanbu, D.; Hari, Y.; Morio, K.; In, Y.; Ishida, T.; Imanishi, T. Tetrahedron Lett. 1997, 38, 8735-8738. (p) Obika, S.; Morio, K.; Nanbu, D.; Imanishi, T. Chem. Commun. 1997, 1643-1644. (q) Obika, S.; Nanbu, D.; Hari, Y.; Andoh, J.; Morio, K.; Doi, T.; Imanishi, T. Tetrahedron Lett. 1998, 39, 5401-5404. (r) Singh, S. K.; Nielsen, P.; Koshkin, A. A.; Wengel, J. Chem. Commun. 1998, 455-456. (s) Koshkin, A. A.; Singh, S. K.; Nielsen, P.; Rajwanshi, V. K.; Kumar, R.; Meldgaard, M.; Olsen, C. E.; Wengel, J. Tetrahedron 1998, 54, 3607-3630. (t) Christensen, N. K.; Petersen, M.; Nielsen, P.; Jacobsen, J. P.; Olsen, C. E.; Wengel, J. J. Am. Chem. Soc. 1998, 120, 5458- 5463. (u) Wang, G.; Gunic, E.; Girardet, J.-L.; Stoisavljevic, V. Bioorg. Med. Chem. Lett. 1999, 9, 1147-1150.
41. In connection with the present study, there have been reported conformationally locked nucleosides: (a) Tarköy, M.; Bolli, M.; Schweizer, B.: Leumann, C. Helv. Chim. Acta 1993, 76, 481-510. (b) Egli, M.; Lubini, P.; Bolli, M.; Dobler, M.; Leumann, C. J. Am. Chem. Soc. 1993, 115, 5855-5856. (c) Tarköy, M.; Leumann, C. Angew. Chem., Int. Ed. Engl. 1993, 32, 1432-1434. (d) Tarköy, M.; Bolli, M.; Leumann, C. Helv. Chim. Acta 1994, 77, 716-744. (e) Bolli, M.; Lubini, P.; Leumann, C. Helv. Chim. Acta 1995, 78, 2077-2096. (f) Litten, C. J.; Epple, C.; Leumann, C. J.; Bioorg. Med. Chem. Lett. 1995, 5, 1231- 1234. (g) Litten, J. C.; Leumann, C. Helv. Chim. Acta 1996, 79, 1129- 1146. (h) Jones, R. J.; Swaminathan, S.; Milligan, J. F.; Wadwani, S.; Froehler, B. C.; Matteucci, M. D. J. Am. Chem. Soc. 1993, 115, 9816- 9817. (i) Zou, R.; Matteucci, M. D. Tetrahedron Lett. 1996, 37, 941-944. (j) Altmann, K.-H.; Kesselring, R.; Francotte, E.; Rihs, G. Tetrahedron Lett. 1994, 35, 2331-2334. (k) Altmann, K.-H.; Imwinkelried, R.; Kesselring, R.; Rihs, G. Tetrahedron Lett. 1994, 35, 7625- 7628. (l) Herdewijn, P. Liebigs Ann. 1996, 1337-1348. (m) Egli, M. Angew. Chem., Int. Ed. Engl. 1996, 35, 1894-1909. (n) Ezzitouni, A.; Russ, P.; Marquez, V. E. J. Org. Chem. 1997, 62, 4870-4873. (o) Obika, S.; Nanbu, D.; Hari, Y.; Morio, K.; In, Y.; Ishida, T.; Imanishi, T. Tetrahedron Lett. 1997, 38, 8735-8738. (p) Obika, S.; Morio, K.; Nanbu, D.; Imanishi, T. Chem. Commun. 1997, 1643-1644. (q) Obika, S.; Nanbu, D.; Hari, Y.; Andoh, J.; Morio, K.; Doi, T.; Imanishi, T. Tetrahedron Lett. 1998, 39, 5401-5404. (r) Singh, S. K.; Nielsen, P.; Koshkin, A. A.; Wengel, J. Chem. Commun. 1998, 455-456. (s) Koshkin, A. A.; Singh, S. K.; Nielsen, P.; Rajwanshi, V. K.; Kumar, R.; Meldgaard, M.; Olsen, C. E.; Wengel, J. Tetrahedron 1998, 54, 3607-3630. (t) Christensen, N. K.; Petersen, M.; Nielsen, P.; Jacobsen, J. P.; Olsen, C. E.; Wengel, J. J. Am. Chem. Soc. 1998, 120, 5458- 5463. (u) Wang, G.; Gunic, E.; Girardet, J.-L.; Stoisavljevic, V. Bioorg. Med. Chem. Lett. 1999, 9, 1147-1150.
42. In connection with the present study, there have been reported conformationally locked nucleosides: (a) Tarköy, M.; Bolli, M.; Schweizer, B.: Leumann, C. Helv. Chim. Acta 1993, 76, 481-510. (b) Egli, M.; Lubini, P.; Bolli, M.; Dobler, M.; Leumann, C. J. Am. Chem. Soc. 1993, 115, 5855-5856. (c) Tarköy, M.; Leumann, C. Angew. Chem., Int. Ed. Engl. 1993, 32, 1432-1434. (d) Tarköy, M.; Bolli, M.; Leumann, C. Helv. Chim. Acta 1994, 77, 716-744. (e) Bolli, M.; Lubini, P.; Leumann, C. Helv. Chim. Acta 1995, 78, 2077-2096. (f) Litten, C. J.; Epple, C.; Leumann, C. J.; Bioorg. Med. Chem. Lett. 1995, 5, 1231- 1234. (g) Litten, J. C.; Leumann, C. Helv. Chim. Acta 1996, 79, 1129- 1146. (h) Jones, R. J.; Swaminathan, S.; Milligan, J. F.; Wadwani, S.; Froehler, B. C.; Matteucci, M. D. J. Am. Chem. Soc. 1993, 115, 9816- 9817. (i) Zou, R.; Matteucci, M. D. Tetrahedron Lett. 1996, 37, 941- 944. (j) Altmann, K.-H.; Kesselring, R.; Francotte, E.; Rihs, G. Tetrahedron Lett. 1994, 35, 2331-2334. (k) Altmann, K.-H.; Imwinkelried, R.; Kesselring, R.; Rihs, G. Tetrahedron Lett. 1994, 35, 7625- 7628. (l) Herdewijn, P. Liebigs Ann. 1996, 1337-1348. (m) Egli, M. Angew. Chem., Int. Ed. Engl. 1996, 35, 1894-1909. (n) Ezzitouni, A.; Russ, P.; Marquez, V. E. J. Org. Chem. 1997, 62, 4870-4873. (o) Obika, S.; Nanbu, D.; Hari, Y.; Morio, K.; In, Y.; Ishida, T.; Imanishi, T. Tetrahedron Lett. 1997, 38, 8735-8738. (p) Obika, S.; Morio, K.; Nanbu, D.; Imanishi, T. Chem. Commun. 1997, 1643-1644. (q) Obika, S.; Nanbu, D.; Hari, Y.; Andoh, J.; Morio, K.; Doi, T.; Imanishi, T. Tetrahedron Lett. 1998, 39, 5401-5404. (r) Singh, S. K.; Nielsen, P.; Koshkin, A. A.; Wengel, J. Chem. Commun. 1998, 455-456. (s) Koshkin, A. A.; Singh, S. K.; Nielsen, P.; Rajwanshi, V. K.; Kumar, R.; Meldgaard, M.; Olsen, C. E.; Wengel, J. Tetrahedron 1998, 54, 3607-3630. (t) Christensen, N. K.; Petersen, M.; Nielsen, P.; Jacobsen, J. P.; Olsen, C. E.; Wengel, J. J. Am. Chem. Soc. 1998, 120, 5458- 5463. (u) Wang, G.; Gunic, E.; Girardet, J.-L.; Stoisavljevic, V. Bioorg. Med. Chem. Lett. 1999, 9, 1147-1150.
43. In connection with the present study, there have been reported conformationally locked nucleosides: (a) Tarköy, M.; Bolli, M.; Schweizer, B.: Leumann, C. Helv. Chim. Acta 1993, 76, 481-510. (b) Egli, M.; Lubini, P.; Bolli, M.; Dobler, M.; Leumann, C. J. Am. Chem. Soc. 1993, 115, 5855-5856. (c) Tarköy, M.; Leumann, C. Angew. Chem., Int. Ed. Engl. 1993, 32, 1432-1434. (d) Tarköy, M.; Bolli, M.; Leumann, C. Helv. Chim. Acta 1994, 77, 716-744. (e) Bolli, M.; Lubini, P.; Leumann, C. Helv. Chim. Acta 1995, 78, 2077-2096. (f) Litten, C. J.; Epple, C.; Leumann, C. J.; Bioorg. Med. Chem. Lett. 1995, 5, 1231- 1234. (g) Litten, J. C.; Leumann, C. Helv. Chim. Acta 1996, 79, 1129- 1146. (h) Jones, R. J.; Swaminathan, S.; Milligan, J. F.; Wadwani, S.; Froehler, B. C.; Matteucci, M. D. J. Am. Chem. Soc. 1993, 115, 9816- 9817. (i) Zou, R.; Matteucci, M. D. Tetrahedron Lett. 1996, 37, 941- 944. (j) Altmann, K.-H.; Kesselring, R.; Francotte, E.; Rihs, G. Tetrahedron Lett. 1994, 35, 2331-2334. (k) Altmann, K.-H.; Imwinkelried, R.; Kesselring, R.; Rihs, G. Tetrahedron Lett. 1994, 35, 7625-7628. (l) Herdewijn, P. Liebigs Ann. 1996, 1337-1348. (m) Egli, M. Angew. Chem., Int. Ed. Engl. 1996, 35, 1894-1909. (n) Ezzitouni, A.; Russ, P.; Marquez, V. E. J. Org. Chem. 1997, 62, 4870-4873. (o) Obika, S.; Nanbu, D.; Hari, Y.; Morio, K.; In, Y.; Ishida, T.; Imanishi, T. Tetrahedron Lett. 1997, 38, 8735-8738. (p) Obika, S.; Morio, K.; Nanbu, D.; Imanishi, T. Chem. Commun. 1997, 1643-1644. (q) Obika, S.; Nanbu, D.; Hari, Y.; Andoh, J.; Morio, K.; Doi, T.; Imanishi, T. Tetrahedron Lett. 1998, 39, 5401-5404. (r) Singh, S. K.; Nielsen, P.; Koshkin, A. A.; Wengel, J. Chem. Commun. 1998, 455-456. (s) Koshkin, A. A.; Singh, S. K.; Nielsen, P.; Rajwanshi, V. K.; Kumar, R.; Meldgaard, M.; Olsen, C. E.; Wengel, J. Tetrahedron 1998, 54, 3607-3630. (t) Christensen, N. K.; Petersen, M.; Nielsen, P.; Jacobsen, J. P.; Olsen, C. E.; Wengel, J. J. Am. Chem. Soc. 1998, 120, 5458- 5463. (u) Wang, G.; Gunic, E.; Girardet, J.-L.; Stoisavljevic, V. Bioorg. Med. Chem. Lett. 1999, 9, 1147-1150.
44. In connection with the present study, there have been reported conformationally locked nucleosides: (a) Tarköy, M.; Bolli, M.; Schweizer, B.: Leumann, C. Helv. Chim. Acta 1993, 76, 481-510. (b) Egli, M.; Lubini, P.; Bolli, M.; Dobler, M.; Leumann, C. J. Am. Chem. Soc. 1993, 115, 5855-5856. (c) Tarköy, M.; Leumann, C. Angew. Chem., Int. Ed. Engl. 1993, 32, 1432-1434. (d) Tarköy, M.; Bolli, M.; Leumann, C. Helv. Chim. Acta 1994, 77, 716-744. (e) Bolli, M.; Lubini, P.; Leumann, C. Helv. Chim. Acta 1995, 78, 2077-2096. (f) Litten, C. J.; Epple, C.; Leumann, C. J.; Bioorg. Med. Chem. Lett. 1995, 5, 1231- 1234. (g) Litten, J. C.; Leumann, C. Helv. Chim. Acta 1996, 79, 1129- 1146. (h) Jones, R. J.; Swaminathan, S.; Milligan, J. F.; Wadwani, S.; Froehler, B. C.; Matteucci, M. D. J. Am. Chem. Soc. 1993, 115, 9816- 9817. (i) Zou, R.; Matteucci, M. D. Tetrahedron Lett. 1996, 37, 941- 944. (j) Altmann, K.-H.; Kesselring, R.; Francotte, E.; Rihs, G. Tetrahedron Lett. 1994, 35, 2331-2334. (k) Altmann, K.-H.; Imwinkelried, R.; Kesselring, R.; Rihs, G. Tetrahedron Lett. 1994, 35, 7625- 7628. (l) Herdewijn, P. Liebigs Ann. 1996, 1337-1348. (m) Egli, M. Angew. Chem., Int. Ed. Engl. 1996, 35, 1894-1909. (n) Ezzitouni, A.; Russ, P.; Marquez, V. E. J. Org. Chem. 1997, 62, 4870-4873. (o) Obika, S.; Nanbu, D.; Hari, Y.; Morio, K.; In, Y.; Ishida, T.; Imanishi, T. Tetrahedron Lett. 1997, 38, 8735-8738. (p) Obika, S.; Morio, K.; Nanbu, D.; Imanishi, T. Chem. Commun. 1997, 1643-1644. (q) Obika, S.; Nanbu, D.; Hari, Y.; Andoh, J.; Morio, K.; Doi, T.; Imanishi, T. Tetrahedron Lett. 1998, 39, 5401-5404. (r) Singh, S. K.; Nielsen, P.; Koshkin, A. A.; Wengel, J. Chem. Commun. 1998, 455-456. (s) Koshkin, A. A.; Singh, S. K.; Nielsen, P.; Rajwanshi, V. K.; Kumar, R.; Meldgaard, M.; Olsen, C. E.; Wengel, J. Tetrahedron 1998, 54, 3607-3630. (t) Christensen, N. K.; Petersen, M.; Nielsen, P.; Jacobsen, J. P.; Olsen, C. E.; Wengel, J. J. Am. Chem. Soc. 1998, 120, 5458- 5463. (u) Wang, G.; Gunic, E.; Girardet, J.-L.; Stoisavljevic, V. Bioorg. Med. Chem. Lett. 1999, 9, 1147-1150.
45. In connection with the present study, there have been reported conformationally locked nucleosides: (a) Tarköy, M.; Bolli, M.; Schweizer, B.: Leumann, C. Helv. Chim. Acta 1993, 76, 481-510. (b) Egli, M.; Lubini, P.; Bolli, M.; Dobler, M.; Leumann, C. J. Am. Chem. Soc. 1993, 115, 5855-5856. (c) Tarköy, M.; Leumann, C. Angew. Chem., Int. Ed. Engl. 1993, 32, 1432-1434. (d) Tarköy, M.; Bolli, M.; Leumann, C. Helv. Chim. Acta 1994, 77, 716-744. (e) Bolli, M.; Lubini, P.; Leumann, C. Helv. Chim. Acta 1995, 78, 2077-2096. (f) Litten, C. J.; Epple, C.; Leumann, C. J.; Bioorg. Med. Chem. Lett. 1995, 5, 1231- 1234. (g) Litten, J. C.; Leumann, C. Helv. Chim. Acta 1996, 79, 1129- 1146. (h) Jones, R. J.; Swaminathan, S.; Milligan, J. F.; Wadwani, S.; Froehler, B. C.; Matteucci, M. D. J. Am. Chem. Soc. 1993, 115, 9816- 9817. (i) Zou, R.; Matteucci, M. D. Tetrahedron Lett. 1996, 37, 941- 944. (j) Altmann, K.-H.; Kesselring, R.; Francotte, E.; Rihs, G. Tetrahedron Lett. 1994, 35, 2331-2334. (k) Altmann, K.-H.; Imwinkelried, R.; Kesselring, R.; Rihs, G. Tetrahedron Lett. 1994, 35, 7625- 7628. (l) Herdewijn, P. Liebigs Ann. 1996, 1337-1348. (m) Egli, M. Angew. Chem., Int. Ed. Engl. 1996, 35, 1894-1909. (n) Ezzitouni, A.; Russ, P.; Marquez, V. E. J. Org. Chem. 1997, 62, 4870-4873. (o) Obika, S.; Nanbu, D.; Hari, Y.; Morio, K.; In, Y.; Ishida, T.; Imanishi, T. Tetrahedron Lett. 1997, 38, 8735-8738. (p) Obika, S.; Morio, K.; Nanbu, D.; Imanishi, T. Chem. Commun. 1997, 1643-1644. (q) Obika, S.; Nanbu, D.; Hari, Y.; Andoh, J.; Morio, K.; Doi, T.; Imanishi, T. Tetrahedron Lett. 1998, 39, 5401-5404. (r) Singh, S. K.; Nielsen, P.; Koshkin, A. A.; Wengel, J. Chem. Commun. 1998, 455-456. (s) Koshkin, A. A.; Singh, S. K.; Nielsen, P.; Rajwanshi, V. K.; Kumar, R.; Meldgaard, M.; Olsen, C. E.; Wengel, J. Tetrahedron 1998, 54, 3607-3630. (t) Christensen, N. K.; Petersen, M.; Nielsen, P.; Jacobsen, J. P.; Olsen, C. E.; Wengel, J. J. Am. Chem. Soc. 1998, 120, 5458- 5463. (u) Wang, G.; Gunic, E.; Girardet, J.-L.; Stoisavljevic, V. Bioorg. Med. Chem. Lett. 1999, 9, 1147-1150.
46. In connection with the present study, there have been reported conformationally locked nucleosides: (a) Tarköy, M.; Bolli, M.; Schweizer, B.: Leumann, C. Helv. Chim. Acta 1993, 76, 481-510. (b) Egli, M.; Lubini, P.; Bolli, M.; Dobler, M.; Leumann, C. J. Am. Chem. Soc. 1993, 115, 5855-5856. (c) Tarköy, M.; Leumann, C. Angew. Chem., Int. Ed. Engl. 1993, 32, 1432-1434. (d) Tarköy, M.; Bolli, M.; Leumann, C. Helv. Chim. Acta 1994, 77, 716-744. (e) Bolli, M.; Lubini, P.; Leumann, C. Helv. Chim. Acta 1995, 78, 2077-2096. (f) Litten, C. J.; Epple, C.; Leumann, C. J.; Bioorg. Med. Chem. Lett. 1995, 5, 1231- 1234. (g) Litten, J. C.; Leumann, C. Helv. Chim. Acta 1996, 79, 1129- 1146. (h) Jones, R. J.; Swaminathan, S.; Milligan, J. F.; Wadwani, S.; Froehler, B. C.; Matteucci, M. D. J. Am. Chem. Soc. 1993, 115, 9816- 9817. (i) Zou, R.; Matteucci, M. D. Tetrahedron Lett. 1996, 37, 941- 944. (j) Altmann, K.-H.; Kesselring, R.; Francotte, E.; Rihs, G. Tetrahedron Lett. 1994, 35, 2331-2334. (k) Altmann, K.-H.; Imwinkelried, R.; Kesselring, R.; Rihs, G. Tetrahedron Lett. 1994, 35, 7625- 7628. (l) Herdewijn, P. Liebigs Ann. 1996, 1337-1348. (m) Egli, M. Angew. Chem., Int. Ed. Engl. 1996, 35, 1894-1909. (n) Ezzitouni, A.; Russ, P.; Marquez, V. E. J. Org. Chem. 1997, 62, 4870-4873. (o) Obika, S.; Nanbu, D.; Hari, Y.; Morio, K.; In, Y.; Ishida, T.; Imanishi, T. Tetrahedron Lett. 1997, 38, 8735-8738. (p) Obika, S.; Morio, K.; Nanbu, D.; Imanishi, T. Chem. Commun. 1997, 1643-1644. (q) Obika, S.; Nanbu, D.; Hari, Y.; Andoh, J.; Morio, K.; Doi, T.; Imanishi, T. Tetrahedron Lett. 1998, 39, 5401-5404. (r) Singh, S. K.; Nielsen, P.; Koshkin, A. A.; Wengel, J. Chem. Commun. 1998, 455-456. (s) Koshkin, A. A.; Singh, S. K.; Nielsen, P.; Rajwanshi, V. K.; Kumar, R.; Meldgaard, M.; Olsen, C. E.; Wengel, J. Tetrahedron 1998, 54, 3607-3630. (t) Christensen, N. K.; Petersen, M.; Nielsen, P.; Jacobsen, J. P.; Olsen, C. E.; Wengel, J. J. Am. Chem. Soc. 1998, 120, 5458- 5463. (u) Wang, G.; Gunic, E.; Girardet, J.-L.; Stoisavljevic, V. Bioorg. Med. Chem. Lett. 1999, 9, 1147-1150.
47. In connection with the present study, there have been reported conformationally locked nucleosides: (a) Tarköy, M.; Bolli, M.; Schweizer, B.: Leumann, C. Helv. Chim. Acta 1993, 76, 481-510. (b) Egli, M.; Lubini, P.; Bolli, M.; Dobler, M.; Leumann, C. J. Am. Chem. Soc. 1993, 115, 5855-5856. (c) Tarköy, M.; Leumann, C. Angew. Chem., Int. Ed. Engl. 1993, 32, 1432-1434. (d) Tarköy, M.; Bolli, M.; Leumann, C. Helv. Chim. Acta 1994, 77, 716-744. (e) Bolli, M.; Lubini, P.; Leumann, C. Helv. Chim. Acta 1995, 78, 2077-2096. (f) Litten, C. J.; Epple, C.; Leumann, C. J.; Bioorg. Med. Chem. Lett. 1995, 5, 1231- 1234. (g) Litten, J. C.; Leumann, C. Helv. Chim. Acta 1996, 79, 1129- 1146. (h) Jones, R. J.; Swaminathan, S.; Milligan, J. F.; Wadwani, S.; Froehler, B. C.; Matteucci, M. D. J. Am. Chem. Soc. 1993, 115, 9816- 9817. (i) Zou, R.; Matteucci, M. D. Tetrahedron Lett. 1996, 37, 941- 944. (j) Altmann, K.-H.; Kesselring, R.; Francotte, E.; Rihs, G. Tetrahedron Lett. 1994, 35, 2331-2334. (k) Altmann, K.-H.; Imwinkelried, R.; Kesselring, R.; Rihs, G. Tetrahedron Lett. 1994, 35, 7625- 7628. (l) Herdewijn, P. Liebigs Ann. 1996, 1337-1348. (m) Egli, M. Angew. Chem., Int. Ed. Engl. 1996, 35, 1894-1909. (n) Ezzitouni, A.; Russ, P.; Marquez, V. E. J. Org. Chem. 1997, 62, 4870-4873. (o) Obika, S.; Nanbu, D.; Hari, Y.; Morio, K.; In, Y.; Ishida, T.; Imanishi, T. Tetrahedron Lett. 1997, 38, 8735-8738. (p) Obika, S.; Morio, K.; Nanbu, D.; Imanishi, T. Chem. Commun. 1997, 1643-1644. (q) Obika, S.; Nanbu, D.; Hari, Y.; Andoh, J.; Morio, K.; Doi, T.; Imanishi, T. Tetrahedron Lett. 1998, 39, 5401-5404. (r) Singh, S. K.; Nielsen, P.; Koshkin, A. A.; Wengel, J. Chem. Commun. 1998, 455-456. (s) Koshkin, A. A.; Singh, S. K.; Nielsen, P.; Rajwanshi, V. K.; Kumar, R.; Meldgaard, M.; Olsen, C. E.; Wengel, J. Tetrahedron 1998, 54, 3607-3630. (t) Christensen, N. K.; Petersen, M.; Nielsen, P.; Jacobsen, J. P.; Olsen, C. E.; Wengel, J. J. Am. Chem. Soc. 1998, 120, 5458- 5463. (u) Wang, G.; Gunic, E.; Girardet, J.-L.; Stoisavljevic, V. Bioorg. Med. Chem. Lett. 1999, 9, 1147-1150.
48. In connection with the present study, there have been reported conformationally locked nucleosides: (a) Tarköy, M.; Bolli, M.; Schweizer, B.: Leumann, C. Helv. Chim. Acta 1993, 76, 481-510. (b) Egli, M.; Lubini, P.; Bolli, M.; Dobler, M.; Leumann, C. J. Am. Chem. Soc. 1993, 115, 5855-5856. (c) Tarköy, M.; Leumann, C. Angew. Chem., Int. Ed. Engl. 1993, 32, 1432-1434. (d) Tarköy, M.; Bolli, M.; Leumann, C. Helv. Chim. Acta 1994, 77, 716-744. (e) Bolli, M.; Lubini, P.; Leumann, C. Helv. Chim. Acta 1995, 78, 2077-2096. (f) Litten, C. J.; Epple, C.; Leumann, C. J.; Bioorg. Med. Chem. Lett. 1995, 5, 1231- 1234. (g) Litten, J. C.; Leumann, C. Helv. Chim. Acta 1996, 79, 1129- 1146. (h) Jones, R. J.; Swaminathan, S.; Milligan, J. F.; Wadwani, S.; Froehler, B. C.; Matteucci, M. D. J. Am. Chem. Soc. 1993, 115, 9816- 9817. (i) Zou, R.; Matteucci, M. D. Tetrahedron Lett. 1996, 37, 941- 944. (j) Altmann, K.-H.; Kesselring, R.; Francotte, E.; Rihs, G. Tetrahedron Lett. 1994, 35, 2331-2334. (k) Altmann, K.-H.; Imwinkelried, R.; Kesselring, R.; Rihs, G. Tetrahedron Lett. 1994, 35, 7625- 7628. (l) Herdewijn, P. Liebigs Ann. 1996, 1337-1348. (m) Egli, M. Angew. Chem., Int. Ed. Engl. 1996, 35, 1894-1909. (n) Ezzitouni, A.; Russ, P.; Marquez, V. E. J. Org. Chem. 1997, 62, 4870-4873. (o) Obika, S.; Nanbu, D.; Hari, Y.; Morio, K.; In, Y.; Ishida, T.; Imanishi, T. Tetrahedron Lett. 1997, 38, 8735-8738. (p) Obika, S.; Morio, K.; Nanbu, D.; Imanishi, T. Chem. Commun. 1997, 1643-1644. (q) Obika, S.; Nanbu, D.; Hari, Y.; Andoh, J.; Morio, K.; Doi, T.; Imanishi, T. Tetrahedron Lett. 1998, 39, 5401-5404. (r) Singh, S. K.; Nielsen, P.; Koshkin, A. A.; Wengel, J. Chem. Commun. 1998, 455-456. (s) Koshkin, A. A.; Singh, S. K.; Nielsen, P.; Rajwanshi, V. K.; Kumar, R.; Meldgaard, M.; Olsen, C. E.; Wengel, J. Tetrahedron 1998, 54, 3607-3630. (t) Christensen, N. K.; Petersen, M.; Nielsen, P.; Jacobsen, J. P.; Olsen, C. E.; Wengel, J. J. Am. Chem. Soc. 1998, 120, 5458- 5463. (u) Wang, G.; Gunic, E.; Girardet, J.-L.; Stoisavljevic, V. Bioorg. Med. Chem. Lett. 1999, 9, 1147-1150.
49. In connection with the present study, there have been reported conformationally locked nucleosides: (a) Tarköy, M.; Bolli, M.; Schweizer, B.: Leumann, C. Helv. Chim. Acta 1993, 76, 481-510. (b) Egli, M.; Lubini, P.; Bolli, M.; Dobler, M.; Leumann, C. J. Am. Chem. Soc. 1993, 115, 5855-5856. (c) Tarköy, M.; Leumann, C. Angew. Chem., Int. Ed. Engl. 1993, 32, 1432-1434. (d) Tarköy, M.; Bolli, M.; Leumann, C. Helv. Chim. Acta 1994, 77, 716-744. (e) Bolli, M.; Lubini, P.; Leumann, C. Helv. Chim. Acta 1995, 78, 2077-2096. (f) Litten, C. J.; Epple, C.; Leumann, C. J.; Bioorg. Med. Chem. Lett. 1995, 5, 1231- 1234. (g) Litten, J. C.; Leumann, C. Helv. Chim. Acta 1996, 79, 1129- 1146. (h) Jones, R. J.; Swaminathan, S.; Milligan, J. F.; Wadwani, S.; Froehler, B. C.; Matteucci, M. D. J. Am. Chem. Soc. 1993, 115, 9816- 9817. (i) Zou, R.; Matteucci, M. D. Tetrahedron Lett. 1996, 37, 941- 944. (j) Altmann, K.-H.; Kesselring, R.; Francotte, E.; Rihs, G. Tetrahedron Lett. 1994, 35, 2331-2334. (k) Altmann, K.-H.; Imwinkelried, R.; Kesselring, R.; Rihs, G. Tetrahedron Lett. 1994, 35, 7625- 7628. (l) Herdewijn, P. Liebigs Ann. 1996, 1337-1348. (m) Egli, M. Angew. Chem., Int. Ed. Engl. 1996, 35, 1894-1909. (n) Ezzitouni, A.; Russ, P.; Marquez, V. E. J. Org. Chem. 1997, 62, 4870-4873. (o) Obika, S.; Nanbu, D.; Hari, Y.; Morio, K.; In, Y.; Ishida, T.; Imanishi, T. Tetrahedron Lett. 1997, 38, 8735-8738. (p) Obika, S.; Morio, K.; Nanbu, D.; Imanishi, T. Chem. Commun. 1997, 1643-1644. (q) Obika, S.; Nanbu, D.; Hari, Y.; Andoh, J.; Morio, K.; Doi, T.; Imanishi, T. Tetrahedron Lett. 1998, 39, 5401-5404. (r) Singh, S. K.; Nielsen, P.; Koshkin, A. A.; Wengel, J. Chem. Commun. 1998, 455-456. (s) Koshkin, A. A.; Singh, S. K.; Nielsen, P.; Rajwanshi, V. K.; Kumar, R.; Meldgaard, M.; Olsen, C. E.; Wengel, J. Tetrahedron 1998, 54, 3607-3630. (t) Christensen, N. K.; Petersen, M.; Nielsen, P.; Jacobsen, J. P.; Olsen, C. E.; Wengel, J. J. Am. Chem. Soc. 1998, 120, 5458- 5463. (u) Wang, G.; Gunic, E.; Girardet, J.-L.; Stoisavljevic, V. Bioorg. Med. Chem. Lett. 1999, 9, 1147-1150.
50. In connection with the present study, there have been reported conformationally locked nucleosides: (a) Tarköy, M.; Bolli, M.; Schweizer, B.: Leumann, C. Helv. Chim. Acta 1993, 76, 481-510. (b) Egli, M.; Lubini, P.; Bolli, M.; Dobler, M.; Leumann, C. J. Am. Chem. Soc. 1993, 115, 5855-5856. (c) Tarköy, M.; Leumann, C. Angew. Chem., Int. Ed. Engl. 1993, 32, 1432-1434. (d) Tarköy, M.; Bolli, M.; Leumann, C. Helv. Chim. Acta 1994, 77, 716-744. (e) Bolli, M.; Lubini, P.; Leumann, C. Helv. Chim. Acta 1995, 78, 2077-2096. (f) Litten, C. J.; Epple, C.; Leumann, C. J.; Bioorg. Med. Chem. Lett. 1995, 5, 1231- 1234. (g) Litten, J. C.; Leumann, C. Helv. Chim. Acta 1996, 79, 1129- 1146. (h) Jones, R. J.; Swaminathan, S.; Milligan, J. F.; Wadwani, S.; Froehler, B. C.; Matteucci, M. D. J. Am. Chem. Soc. 1993, 115, 9816- 9817. (i) Zou, R.; Matteucci, M. D. Tetrahedron Lett. 1996, 37, 941- 944. (j) Altmann, K.-H.; Kesselring, R.; Francotte, E.; Rihs, G. Tetrahedron Lett. 1994, 35, 2331-2334. (k) Altmann, K.-H.; Imwinkelried, R.; Kesselring, R.; Rihs, G. Tetrahedron Lett. 1994, 35, 7625- 7628. (l) Herdewijn, P. Liebigs Ann. 1996, 1337-1348. (m) Egli, M. Angew. Chem., Int. Ed. Engl. 1996, 35, 1894-1909. (n) Ezzitouni, A.; Russ, P.; Marquez, V. E. J. Org. Chem. 1997, 62, 4870-4873. (o) Obika, S.; Nanbu, D.; Hari, Y.; Morio, K.; In, Y.; Ishida, T.; Imanishi, T. Tetrahedron Lett. 1997, 38, 8735-8738. (p) Obika, S.; Morio, K.; Nanbu, D.; Imanishi, T. Chem. Commun. 1997, 1643-1644. (q) Obika, S.; Nanbu, D.; Hari, Y.; Andoh, J.; Morio, K.; Doi, T.; Imanishi, T. Tetrahedron Lett. 1998, 39, 5401-5404. (r) Singh, S. K.; Nielsen, P.; Koshkin, A. A.; Wengel, J. Chem. Commun. 1998, 455-456. (s) Koshkin, A. A.; Singh, S. K.; Nielsen, P.; Rajwanshi, V. K.; Kumar, R.; Meldgaard, M.; Olsen, C. E.; Wengel, J. Tetrahedron 1998, 54, 3607-3630. (t) Christensen, N. K.; Petersen, M.; Nielsen, P.; Jacobsen, J. P.; Olsen, C. E.; Wengel, J. J. Am. Chem. Soc. 1998, 120, 5458- 5463. (u) Wang, G.; Gunic, E.; Girardet, J.-L.; Stoisavljevic, V. Bioorg. Med. Chem. Lett. 1999, 9, 1147-1150.
51. In connection with the present study, there have been reported conformationally locked nucleosides: (a) Tarköy, M.; Bolli, M.; Schweizer, B.: Leumann, C. Helv. Chim. Acta 1993, 76, 481-510. (b) Egli, M.; Lubini, P.; Bolli, M.; Dobler, M.; Leumann, C. J. Am. Chem. Soc. 1993, 115, 5855-5856. (c) Tarköy, M.; Leumann, C. Angew. Chem., Int. Ed. Engl. 1993, 32, 1432-1434. (d) Tarköy, M.; Bolli, M.; Leumann, C. Helv. Chim. Acta 1994, 77, 716-744. (e) Bolli, M.; Lubini, P.; Leumann, C. Helv. Chim. Acta 1995, 78, 2077-2096. (f) Litten, C. J.; Epple, C.; Leumann, C. J.; Bioorg. Med. Chem. Lett. 1995, 5, 1231- 1234. (g) Litten, J. C.; Leumann, C. Helv. Chim. Acta 1996, 79, 1129- 1146. (h) Jones, R. J.; Swaminathan, S.; Milligan, J. F.; Wadwani, S.; Froehler, B. C.; Matteucci, M. D. J. Am. Chem. Soc. 1993, 115, 9816- 9817. (i) Zou, R.; Matteucci, M. D. Tetrahedron Lett. 1996, 37, 941- 944. (j) Altmann, K.-H.; Kesselring, R.; Francotte, E.; Rihs, G. Tetrahedron Lett. 1994, 35, 2331-2334. (k) Altmann, K.-H.; Imwinkelried, R.; Kesselring, R.; Rihs, G. Tetrahedron Lett. 1994, 35, 7625- 7628. (l) Herdewijn, P. Liebigs Ann. 1996, 1337-1348. (m) Egli, M. Angew. Chem., Int. Ed. Engl. 1996, 35, 1894-1909. (n) Ezzitouni, A.; Russ, P.; Marquez, V. E. J. Org. Chem. 1997, 62, 4870-4873. (o) Obika, S.; Nanbu, D.; Hari, Y.; Morio, K.; In, Y.; Ishida, T.; Imanishi, T. Tetrahedron Lett. 1997, 38, 8735-8738. (p) Obika, S.; Morio, K.; Nanbu, D.; Imanishi, T. Chem. Commun. 1997, 1643-1644. (q) Obika, S.; Nanbu, D.; Hari, Y.; Andoh, J.; Morio, K.; Doi, T.; Imanishi, T. Tetrahedron Lett. 1998, 39, 5401-5404. (r) Singh, S. K.; Nielsen, P.; Koshkin, A. A.; Wengel, J. Chem. Commun. 1998, 455-456. (s) Koshkin, A. A.; Singh, S. K.; Nielsen, P.; Rajwanshi, V. K.; Kumar, R.; Meldgaard, M.; Olsen, C. E.; Wengel, J. Tetrahedron 1998, 54, 3607-3630. (t) Christensen, N. K.; Petersen, M.; Nielsen, P.; Jacobsen, J. P.; Olsen, C. E.; Wengel, J. J. Am. Chem. Soc. 1998, 120, 5458- 5463. (u) Wang, G.; Gunic, E.; Girardet, J.-L.; Stoisavljevic, V. Bioorg. Med. Chem. Lett. 1999, 9, 1147-1150.
52. In connection with the present study, there have been reported conformationally locked nucleosides: (a) Tarköy, M.; Bolli, M.; Schweizer, B.: Leumann, C. Helv. Chim. Acta 1993, 76, 481-510. (b) Egli, M.; Lubini, P.; Bolli, M.; Dobler, M.; Leumann, C. J. Am. Chem. Soc. 1993, 115, 5855-5856. (c) Tarköy, M.; Leumann, C. Angew. Chem., Int. Ed. Engl. 1993, 32, 1432-1434. (d) Tarköy, M.; Bolli, M.; Leumann, C. Helv. Chim. Acta 1994, 77, 716-744. (e) Bolli, M.; Lubini, P.; Leumann, C. Helv. Chim. Acta 1995, 78, 2077-2096. (f) Litten, C. J.; Epple, C.; Leumann, C. J.; Bioorg. Med. Chem. Lett. 1995, 5, 1231- 1234. (g) Litten, J. C.; Leumann, C. Helv. Chim. Acta 1996, 79, 1129- 1146. (h) Jones, R. J.; Swaminathan, S.; Milligan, J. F.; Wadwani, S.; Froehler, B. C.; Matteucci, M. D. J. Am. Chem. Soc. 1993, 115, 9816- 9817. (i) Zou, R.; Matteucci, M. D. Tetrahedron Lett. 1996, 37, 941- 944. (j) Altmann, K.-H.; Kesselring, R.; Francotte, E.; Rihs, G. Tetrahedron Lett. 1994, 35, 2331-2334. (k) Altmann, K.-H.; Imwinkelried, R.; Kesselring, R.; Rihs, G. Tetrahedron Lett. 1994, 35, 7625- 7628. (l) Herdewijn, P. Liebigs Ann. 1996, 1337-1348. (m) Egli, M. Angew. Chem., Int. Ed. Engl. 1996, 35, 1894-1909. (n) Ezzitouni, A.; Russ, P.; Marquez, V. E. J. Org. Chem. 1997, 62, 4870-4873. (o) Obika, S.; Nanbu, D.; Hari, Y.; Morio, K.; In, Y.; Ishida, T.; Imanishi, T. Tetrahedron Lett. 1997, 38, 8735-8738. (p) Obika, S.; Morio, K.; Nanbu, D.; Imanishi, T. Chem. Commun. 1997, 1643-1644. (q) Obika, S.; Nanbu, D.; Hari, Y.; Andoh, J.; Morio, K.; Doi, T.; Imanishi, T. Tetrahedron Lett. 1998, 39, 5401-5404. (r) Singh, S. K.; Nielsen, P.; Koshkin, A. A.; Wengel, J. Chem. Commun. 1998, 455-456. (s) Koshkin, A. A.; Singh, S. K.; Nielsen, P.; Rajwanshi, V. K.; Kumar, R.; Meldgaard, M.; Olsen, C. E.; Wengel, J. Tetrahedron 1998, 54, 3607-3630. (t) Christensen, N. K.; Petersen, M.; Nielsen, P.; Jacobsen, J. P.; Olsen, C. E.; Wengel, J. J. Am. Chem. Soc. 1998, 120, 5458-5463. (u) Wang, G.; Gunic, E.; Girardet, J.-L.; Stoisavljevic, V. Bioorg. Med. Chem. Lett. 1999, 9, 1147-1150.
53. In connection with the present study, there have been reported conformationally locked nucleosides: (a) Tarköy, M.; Bolli, M.; Schweizer, B.: Leumann, C. Helv. Chim. Acta 1993, 76, 481-510. (b) Egli, M.; Lubini, P.; Bolli, M.; Dobler, M.; Leumann, C. J. Am. Chem. Soc. 1993, 115, 5855-5856. (c) Tarköy, M.; Leumann, C. Angew. Chem., Int. Ed. Engl. 1993, 32, 1432-1434. (d) Tarköy, M.; Bolli, M.; Leumann, C. Helv. Chim. Acta 1994, 77, 716-744. (e) Bolli, M.; Lubini, P.; Leumann, C. Helv. Chim. Acta 1995, 78, 2077-2096. (f) Litten, C. J.; Epple, C.; Leumann, C. J.; Bioorg. Med. Chem. Lett. 1995, 5, 1231- 1234. (g) Litten, J. C.; Leumann, C. Helv. Chim. Acta 1996, 79, 1129- 1146. (h) Jones, R. J.; Swaminathan, S.; Milligan, J. F.; Wadwani, S.; Froehler, B. C.; Matteucci, M. D. J. Am. Chem. Soc. 1993, 115, 9816- 9817. (i) Zou, R.; Matteucci, M. D. Tetrahedron Lett. 1996, 37, 941- 944. (j) Altmann, K.-H.; Kesselring, R.; Francotte, E.; Rihs, G. Tetrahedron Lett. 1994, 35, 2331-2334. (k) Altmann, K.-H.; Imwinkelried, R.; Kesselring, R.; Rihs, G. Tetrahedron Lett. 1994, 35, 7625- 7628. (l) Herdewijn, P. Liebigs Ann. 1996, 1337-1348. (m) Egli, M. Angew. Chem., Int. Ed. Engl. 1996, 35, 1894-1909. (n) Ezzitouni, A.; Russ, P.; Marquez, V. E. J. Org. Chem. 1997, 62, 4870-4873. (o) Obika, S.; Nanbu, D.; Hari, Y.; Morio, K.; In, Y.; Ishida, T.; Imanishi, T. Tetrahedron Lett. 1997, 38, 8735-8738. (p) Obika, S.; Morio, K.; Nanbu, D.; Imanishi, T. Chem. Commun. 1997, 1643-1644. (q) Obika, S.; Nanbu, D.; Hari, Y.; Andoh, J.; Morio, K.; Doi, T.; Imanishi, T. Tetrahedron Lett. 1998, 39, 5401-5404. (r) Singh, S. K.; Nielsen, P.; Koshkin, A. A.; Wengel, J. Chem. Commun. 1998, 455-456. (s) Koshkin, A. A.; Singh, S. K.; Nielsen, P.; Rajwanshi, V. K.; Kumar, R.; Meldgaard, M.; Olsen, C. E.; Wengel, J. Tetrahedron 1998, 54, 3607-3630. (t) Christensen, N. K.; Petersen, M.; Nielsen, P.; Jacobsen, J. P.; Olsen, C. E.; Wengel, J. J. Am. Chem. Soc. 1998, 120, 5458- 5463. (u) Wang, G.; Gunic, E.; Girardet, J.-L.; Stoisavljevic, V. Bioorg. Med. Chem. Lett. 1999, 9, 1147-1150.