Bhisetti Govinda Rao

Design and synthesis of novel conformationally restricted HIV protease inhibitors

A set of HIV protease inhibitors represented by compound 2 has previously been described. Structural and conformational analysis of this compound suggested that conformational restriction of the P1/P2 portion of the molecule could lead to a novel set of potent protease inhibitors. Thus, probe compounds 3-7 were designed, synthesized, and found to be potent inhibitors of HIV protease.

Characterization of V36C, a Novel Amino Acid Substitution Conferring Hepatitis C Virus (HCV) Resistance to Telaprevir, a Potent Peptidomimetic Inhibitor of HCV Protease

ABSTRACT We characterized a novel substitution conferring moderate resistance to telaprevir, a peptidomimetic inhibitor of hepatitis C virus protease. V36C conferred a 4.0-fold increase in the telaprevir 50% inhibitory concentration in an enzyme assay and a 9.5-fold increase in the replicon model. The replication capacity of a replicon harboring V36C was close to that of the wild-type protease. This case emphasizes the complexity of hepatitis C virus resistance to protease inhibitors.

Design, synthesis, and conformational analysis of a novel series of HIV protease inhibitors

A combination of structure-based design and both solution, and solid-phase synthesis were utilized to derive a potent (nM) series of HIV-1 protease inhibitors bearing a structurally novel backbone. Detailed structural analysis of several inhibitors prepared in this series has suggested that rigidification of the P1/P2 region of this class of molecules may result in compounds with improved potency.

Cocrystalline Solids of Telaprevir with Enhanced Oral Absorption

A combination of coformer screening and modeling, followed by characterization using calorimetry, structure elucidation, and solubility led to the identification of novel crystalline forms of the hepatitis C protease inhibitor, telaprevir. The lead crystalline form, a cocrystalline solid of telaprevir with 4-aminosalycilic acid, was identified among the list of possible cocrystals via modeling and confirmed by initial screening. It displayed the most significant aqueous solubility improvement over the neat crystalline form. Enhancement of in vivo performance was further demonstrated: a 10-fold increase in bioavailability was achieved for the cocrystal in comparison to the neat nanocrystalline telaprevir and it was found to be not statistically different from the lead amorphous spray-dried formulation.