Patent ID: 6933396

Claim:
A process for preparing a substantially optically pure psorospermin or analog of the formula: wherein each of R 1 and R 3 is H or alkyl; wherein R 2 is H, OH, substituted or unsubstituted alkyl, OR 2 ′, wherein the substituted alkyl is 1-6C alkyl substituted with —COOR 7 , —≡N, or heteroalkyl, wherein R 7 is H or alkyl, and wherein R 2 ′ is alkyl or a protecting group; wherein each of R 4 , R 5 , and R 6 is H, alkyl, or 2-10C alkoxy; wherein two adjacent residues of R 2 , R 4 , R 5 , and R 6 can form a fused cyclic, aromatic, heteroaromatic or heterocyclic ring having 5-7 members, the process comprising: deprotecting a compound of the formula: wherein R 1 and R 3 -R 6 are defined above, R 2 is H, alkyl, O-alkyl, or an O-protecting group, Prot is a protecting group, and Lv is a leaving group.