Design and SAR of macrocyclic Hsp90 inhibitors with increased metabolic stability and potent cell-proliferation activity.

A novel series of macrocyclic ortho-aminobenzamide Hsp90 inhibitors is reported. A basic nitrogen within the tether linking the aniline nitrogen atom to a tetrahydroindolone moiety allowed access to compounds with good physical properties. Important structure-activity relationship information was obtained from this series which led to the discovery of a soluble and stable compound which is potent in an Hsp90 binding and cell-proliferation assay.

Synthesis and PKCtheta inhibitory activity of a series of 5-vinyl phenyl sulfonamide-3-pyridinecarbonitriles.

A series of 5-vinyl phenyl sulfonamide-3-pyridinecarbonitriles were prepared and evaluated as PKCtheta inhibitors. Optimization resulted in the identification of compound 15 with an IC(50) value 0.44 nM for the inhibition of PKCtheta with 150-fold selectivity over PKCdelta.

First generation 5-vinyl-3-pyridinecarbonitrile PKCtheta inhibitors.

A series of 5-vinyl-3-pyridinecarbonitriles were synthesized and evaluated as PKCtheta inhibitors. The systematic optimization of 4-[(4-methyl-1H-indol-5-yl)amino]-5-[(E)-2-phenylvinyl]-3-pyridinecarbonitrile 3 resulted in the identification of compound 23e as a potent PKCtheta inhibitor with good selectivity over PKCdelta.

Direct oxa-Pictet-Spengler cyclization to the natural (3a,5)-trans-stereochemistry in the syntheses of (+)-7-deoxyfrenolicin B and (+)-7-deoxykalafungin.

The pyranonaphthoquinones (+)-7-deoxyfrenolicin B and (+)-7-deoxykalafungin were synthesized in four steps using an oxa-Pictet-Spengler cyclization that directly provided the natural (3a,5)-trans-substituted dihydronaphthopyrans with high diastereoselectivity. This outcome is in contrast to the unnatural (3a,5)-cis-substituted dihydronaphthopyrans reported under similar conditions for the syntheses of (+)-frenolicin B and (+)-kalafungin. Computational modeling is presented that provides insight into this unusual stereoselectivity.