Epoxidation of cis-3,4-bis(benzyloxymethyl)cyclobut-1-ene 4 gave compounds 7a and 7b which were separated Reaction of the cis-epoxide 7a with adenine led to the N-9 and N-7 attack products, 10a and 10b, respectively. In the same conditions, the trans-epoxide 7b yielded the N-9 product 12. Nucleoside analogues 11 and 13 were obtained by debenzylation of 10a and 12, respectively.
Synthesis of a novel trisubstituted cyclobutane nucleoside analogue. Unexpected C4-C3 ring contractions in related reactions
作者:Laurence Mévellec、François Huet
DOI:10.1016/s0040-4020(97)00266-4
日期:1997.4
mesylate 5b. On the other hand the same reaction starting from its isomer 5a did not work and led to the surprising ringcontraction products 8a and 8b. Another unexpected ringcontraction leading to 15 was pointed out in the course of preparation of the deuteriated compounds 5a′ and 5a″. Position of deuterium in products 8a′ and 8b′ or 8a″ and 8b″ issued from reactions with 5a′ or 5a″ gave useful mechanistic
High selectivities in electrophilic additions to cyclobutene compounds
作者:Laurence Mévellec、Michel Evers、François Huet
DOI:10.1016/s0040-4020(96)00945-3
日期:1996.11
Epoxidation of 2, 3, 4 with m-CPBA mainly led to the cis-attack products whereas 1 and 6 led to the other selectivity. The result was reversed, from 4, with Payne's reagent Bromohydroxylation of 4 involved an intermediate bromonium ion syn to the substituents. Haloselenylations occurred with the syn-selectivity from 1, 2, 3 and 4, to the anti-selectivity from 6, and without selectivity from 5. NOE enhancement measurements and several chemical correlations led to the stereochemical assignments. Formation of the intramolecular reaction products 24 and 25 was also pointed out. Copyright (C) 1996 Elsevier Science Ltd
Novel cyclobutane carbocyclic nucleosides
作者:Laurence Mévellec、François Huet
DOI:10.1016/s0040-4020(01)89324-8
日期:1994.1
Epoxidation of cis-3,4-bis(benzyloxymethyl)cyclobut-1-ene 4 gave compounds 7a and 7b which were separated Reaction of the cis-epoxide 7a with adenine led to the N-9 and N-7 attack products, 10a and 10b, respectively. In the same conditions, the trans-epoxide 7b yielded the N-9 product 12. Nucleoside analogues 11 and 13 were obtained by debenzylation of 10a and 12, respectively.
Preparation involving a C4-C3 ring contraction in the key step of a novel cyclopropane carbocyclic nucleoside
作者:Laurence Mévellec、François Huet
DOI:10.1016/0040-4039(95)01536-1
日期:1995.10
Cis-3,4-bis(benzyloxymethyl)cyclobut-1-ene 1 mainly led to bromohydrin 5 with a cis relationship between bromine and the benzyloxymethyl groups. The stereospecific ring contraction of 5 afforded aldehyde 7 which could be converted into the nucleoside analogue 1 2.