A novel route is proposed for the synthesis of heterocyclic analogs of the naturally occurring combretastatin A-4 based on the reaction of alpha-acetylenic ketones with polyfunctional nucleophiles (hydroxylamine, hydrazine, guanidine). Previously unknown combretastatin A-4 analogs with azole and azine bridges were obtained.
A novel route is proposed for the synthesis of heterocyclic analogs of the naturally occurring combretastatin A-4 based on the reaction of alpha-acetylenic ketones with polyfunctional nucleophiles (hydroxylamine, hydrazine, guanidine). Previously unknown combretastatin A-4 analogs with azole and azine bridges were obtained.
New transformation of α-acetylenic ketones under the action of 1,2-diaminoethane
作者:M. P. Davydova、S. F. Vasilevskii、G. A. Tolstikov
DOI:10.1007/s11172-011-0030-1
日期:2011.1
A reaction of 3-aryl-1-(3,4,5-trimethoxyphenyl)prop-2-yn-1-ones with 1,2-diaminoethane in boiling dioxane leads to 2-aryl-4,5-dihydro-1H-imidazoles and 1-(3,4,5-trimethoxy-phenyl)ethanone.
Dissecting Alkynes: Full Cleavage of Polarized C≡C Moiety via Sequential Bis-Michael Addition/Retro-Mannich Cascade
作者:Saumya Roy、Maria P. Davydova、Runa Pal、Kerry Gilmore、Genrikh A. Tolstikov、Sergei F. Vasilevsky、Igor V. Alabugin
DOI:10.1021/jo201259j
日期:2011.9.16
The reaction of diaryl ketoalkynes with 1,2-diamino ethane leads to e full scission of the triple bond with the formation of acetophenone and imidazoline fragments. In this transformation, one of the alkyne carbons undergoes formal reduction with the formation of three C-H bonds, whereas the other carbon undergoes formal oxidation via the formation of three C-N bonds (one pi and two sigma). Computational analysis confirmed that the key fragmentation step proceeds via a six-membered TS in a concerted manner. Both amines are involved in the fragmentation: the N-H moiety of one amine transfers a proton to the developing negative charge at the enolate oxygen, while the other amine provides direct stereoelectronic assistance to the C-C bond cleavage via a hyperconjugative n(N)->sigma*(C-C) interaction.
Reaction of α,β-alkynylketones with β-amino alcohols: pseudoephedrine- assisted cleavage of triple bond via formal internal redox process
作者:Sergei F. Vasilevsky、Maria P. Davydova、Victor I. Mamatuyk、Nadezhda V. Pleshkova、Dmitry S. Fadeev、Igor V. Alabugin
DOI:10.1016/j.mencom.2015.09.021
日期:2015.9
Reaction of 3-aryl-1-(3,4,5-trimethoxyphenyl)prop-2-yn-1-ones with (+)-pseudoephedrine leads to products of alkyne moiety cleavage, namely, 1-(3,4,5-trimethoxyphenyl)ethanone and N-(1-hydroxy-1-phenylprop-2-yl)-N-methylbenzamides. In the course of the process one of alkyne carbons undergoes a formal reduction to a Me group, whereas the other one is oxidized to a C(O)NRR' moiety.
Synthesis of new combretastatin A-4 analogues and study of their anti-inflammatory activity
作者:M. P. Davydova、I. V. Sorokina、T. G. Tolstikova、V. I. Mamatyuk、D. S. Fadeev、S. F. Vasilevsky
DOI:10.1134/s1068162015010033
日期:2015.1
A new approach to the synthesis of natural combretastatin A-4 analogues based on the interaction of a- acetylenic ketones with secondary amines (diethyl amine, pyrrolidine, piperidine, morpholine) was proposed. Previously unknown analogues of combretastatin A-4 containing the 13-aminovinylcarbonyl bridges were synthesized. Anti-inflammatory activity of the obtained compounds was studied on models of exudative inflammation caused by histamine or concanavalin A.