An efficient and selective synthesis of nakienone A involving a novel protocol for α-alkenylation of ketones via palladium-catalyzed alkenyl-alkenyl coupling
作者:Milan Pour、Ei-ichi Negishi
DOI:10.1016/s0040-4039(96)02409-4
日期:1997.1
Nakienone A was synthesized for the first time from 3-methoxy-2-cyclopentenone, dienyl iodide 7, and LICH(2)OMOM in 8 steps in 26% overall yield with full control of the alkene geometry using the Pd-catalyzed cross coupling reaction of a cyclopentenylzinc derivative 6a with 7 as a key step. (C) 1997, Elsevier Science Ltd. All rights reserved.
Organozinc reagents are among the most commonly used organometallicreagents in modern synthetic chemistry, and multifunctionalized organozinc reagents can be synthesized from structurally simple, readily available ones by means of alkyne carbozincation. However, this method suffers from poor tolerance for terminal alkynes, and transformation of the newly introduced organic groups is difficult, which
Nakienones A-C and nakitriol, new cytotoxic cyclic C11 metabolites from an okinawan cyanobacterial (Synechocystis sp.) overgrowth of coral
作者:Dale G Nagle、William H Gerwick
DOI:10.1016/0040-4039(94)02397-t
日期:1995.2
Nakienones A-C and nakitriol, a series of reactive cytotoxicmetabolites, were isolated from dead and necrotic branches of stony coral (Acropora sp.) which were completely covered with a gray-black mat of cyanobacteria (Synechocystis sp.). Their structures were determined spectroscopically by interpretation of 2D-NMR experiments, including HMBC and NOESY, and by comparison with model compounds.