William F. Berkowitz

Chiral prostanoid intermediates from aucubin

Abstract Several potentially useful prostanoid intermediates have been prepared from aucubin. Dry DMSO-NBS converts enol ethers to α-bromoesters in one step.

A photochemical approach to the taxanes

The de Mayo sequence has been applied to the inter- and intramolecular photocycloaddition of various cycloalkenes with homocamphorquinone derivatives to generate a model for the A,B, and C rings of the Taxanes.

An approach to the d-ring of baccatin III (taxol, cephalomannine).

Abstract We report a sequence of reactions applicable to the construction of the oxetane (D-Ring)/tertiary acetate grouping of Baccatin III (Taxol, Cephalomannine).

Copper-catalyzed cross-coupling of alkylsamarium reagents with alkyl halides

Abstract SmI 2 /HMPA converts alkyl iodides and bromides to alkyl samarium reagents which can be cross-coupled with primary alkyl iodides and bromides and secondary iodides in the presence of Cu(I) halides or Li 2 CuCl 4 at room temperature. The alkylation of primary iodides gives good yields of cross-coupling products with negligible homo-coupling products. The method is especially useful for the small scale cross-coupling reactions.

Synthesis of archaebacterial lipid C20 chirons

Abstract Archaebacterial lipid C 20 chirons were synthesized by cross-coupling optically active C 10 “dimer” units prepared from hydroxyester 7 . Vitamin E (C 15 ) side chain was similarly constructed.

The conversion of asperuloside to an optically active prostaglandin intermediate

Synthesis of optically active intermediate 1a for PGF2α or (+)-11-deoxy-11α-hydroxymethyl PGF2α from asperuloside is described.