Liver X receptors are nuclear receptors that regulate metabolism of cholesterol. They are activated by oxysterols resulting in increased transcription of the ABCA1 gene, promoting cholesterol efflux and HDL formation. We have identified podocarpic acid anhydride as a 1nM agonist of LXRalpha and beta receptors. Functionally this agonist was over 8-10-fold better activator of LXR receptors compared to one of the natural ligands, 22-(R)-hydroxy cholesterol, in HEK-293 cells. An imide analog increased the level of HDL by 26%, decreased LDL by 10.6%, and increased triglyceride by 51% in hamsters. Discovery, synthesis, SAR and details of the activities of dimers have been described.

Bioconversion of taxol/cephalomannine by Streptomyces sp. MA 7065 resulted in hydroxylation on the 10-acetyl methyl group in 60% yield and on the benzene ring at the para position of the phenylisoserine side chain in 10% yield. This culture could also hydroxylate the allylic methyl group of the phenylisoserine side chain of cephalomannine quantitatively. All three metabolites were cytotoxic toward human lung, breast and colon tumor cell lines.