Asymmetric synthesis of bryostatin 2

Angewandte Chemie - International Edition

Volumn 37, Issue 17, 1998, Pages 2354-2359

  Evans, David A ^a   Carter, Percy H ^a   Carreira, Erick M ^a   Prunet, Joëlle A ^a   Charette, André B ^a   Lautens, Mark ^a  

^a HARVARD UNIVERSITY   (United States)

Author keywords

Aldol reactions; Antitumor agents; Bryostatin; Total synthesis

Indexed keywords

EID: 0032544464     PISSN: 14337851     EISSN: None     Source Type: Journal    
DOI: 10.1002/(SICI)1521-3773(19980918)37:17<2354::AID-ANIE2354>3.0.CO;2-9     Document Type: Article

References (48)

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10. Abbreviations: Bn=benzyl; Boc=tert-butoxycarbonyl; CSA= camphorsulfonic acid; DDQ=2,3-dichloro-5,6-dicyanoquinone; DIBALH=diisobutylaluminum hydride; DIC=diisopropylcarbodiimide; DIPCI=B-chlorodiisopinocampheylborane; DMAP=4-dimethylaminopyridine; d.r.=diastereomer ratio; HMDS=bis(trimethylsilyl)amide; im=imidazole; LG=leaving group; 2,6-lut= 2,6-lutidine; MAc=methoxyacetate; mCPBA=meta-chloroperoxybenzoic acid; PMB=para-methoxybenzyl; PMP=para-methoxyphenyl; PNBz=para-nitrobenzoate; PPTS=pyridinium p-toluenesulfonate; pyr=pyridine; TBAF=tetrabutylammonium fluoride; TBS=tert-butyldimethylsilyl; TES=triethylsilyl; Tf=trifluoromethanesulfonyl; TMS=trimethylsilyl; Ts=p-toluenesulfonyl.
11. 2, -78°C.
12. 2, -78°C.
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28. a) Fortuitously, this is an example of a "matched" double diastereodifferentiating reaction.
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42. 6]acetone).
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47. Prepared in good yield from 2-hexenal according to the method of Coutrot et al.: P. Coutrot, M. Snoussi, P. Savignac, Synthesis 1978, 133-134.
48. We thank Prof. G. R. Pettit for providing us with a natural sample of bryostatin 2.