213740-16-0Relevant academic research and scientific papers
Studies towards the total synthesis of (-)-callystatin A
Yadav,Yadagiri,Madhuri, Ch.,Sabitha
, p. 4269 - 4272 (2011/09/12)
The synthesis of C1-C12 and C13-C 22 fragments of (-)-callystatin A is accomplished employing desymmetrization strategy for the creation of five chiral centres of the polypropionate fragment and application of c
A practical synthesis of (-)-kazusamycin A (revised)
Zhou, Shengfeng,Chen, Huaxiang,Liao, Wensheng,Chen, Shu-Hui,Li, Ge,Ando, Ryoichi,Kuwajima, Isao
, p. 6341 - 6344 (2007/10/03)
We describe herein a stereo-controlled and practical synthesis of three key building blocks, namely Segment AB′, Segment D, and Segment E′ needed for the total synthesis of (-)-kazusamycin A.
Asymmetric total synthesis of (-)-callystatin A and (-)-20-epi-callystatin A employing chemical and biological methods
Enders, Dieter,Vicario, Jose L.,Job, Andreas,Wolberg, Michael,Mueller, Michael
, p. 4272 - 4284 (2007/10/03)
An efficient asymmetric total synthesis of the potent cytotoxic marine natural product (-)-callystatin A and its 20-epi analogue has been achieved. The synthetic pathway involved the preparation of three fragments to be coupled with each other at the end of the route. The first fragment 3 was obtained using a biocatalytic enantioselective reduction of a 3,5-dioxocarboxylate as the key step. For the second intermediate 4 the asymmetric α-alkylation of an O-protected derivative of 4-hydroxybutanal was performed exploiting the SAMP/ RAMP hydrazone alkylation methodology, and followed by a highly Z-selective Homer-Wadsworth-Emmons reaction under modified conditions. For the synthesis of the polypropionate fragment 5 a diastereoselective syn-aldol reaction was employed between a chiral ethyl ketone and an α-substituted chiral aldehyde, both prepared in enantiopure form again by means of the asymmetric alkylation of their corresponding RAMP hydrazones. Finally, these three building blocks were coupled using highly E-selective Wittig reactions via allyltributylphosphonium ylides to afford the target compounds after a final oxidation/deprotection sequence.
