Synthesis of the C11-C23 Fragment of the Potent Antitumor Agent Dictyostatin

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)We wish to report here our initial efforts toward the total synthesis of the potent antitumor agent dictyostatin, describing a short and efficient synthesis of the C11-C23 fragment. ( (C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)1014911494FAEP-UNICAMPFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Additional Vinyl Ketones and Their Pyranyl Ketones in Gonyleptid Harvestmen (Arachnida: Opiliones) Suggest These Metabolites Are Widespread in This Family

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Four species of gonyleptid harvestmen, Acanthogonyleptes pulcher, Gonyleptes saprophilus (Gonyleptinae), Sodreana barbiellini, and Sodreana leprevosti (Sodreaninae), were examined by GC-MS and H-1 NMR All of these species release vinyl ketones, and three of them produce the corresponding pyranyl ketones, which are presumed hetero-Diels-Alder (HDA) dimers. The vinyl ketones 5-methyl-1-hexen-3-one, rac-4-methyl-1-hexen-3-one, and (S)-4-methyl-1-hexen-3-one were synthesized. Natural 4-methyl-1-hexen-3-one is present as a single stereoisomer and has the R-configuration. Vinyl ketone dimers (HDA dimers) were also observed in the scent gland exudate and characterized by HRMS, C-13 NMR, and H-1 NMR chemical shifts of the pyranyl moiety.76915591564Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)PetrobrasConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)FAPESP [GM 02/00381-0, 08/06604-7