Stereocontrolled synthesis of a C(1)-C(15) segment for the marine macrolides swinholide A and scytophycin C: use of a vinylogous Mukaiyama aldol reaction
摘要:
The C1-C-15 segment (+/-)-8 of swinholide A/scytophycin C was prepared in eight steps from (E)-4-chlorobut-3-en-2-one (10) in 19% overall yield with 87% diastereoselectivity. The C-7 stereocenter was controlled by the novel, vinylogous Mukaiyama aldol reaction, 16 + 18 --> 19, mediated by BF3.OEt2. The related C1-C-13 segment (+/-)-9 for misakinolide A was also prepared.