Parigi Raghavendar Reddy

New diterpenoids from Caesalpinia species and their cytotoxic activity.

Chemical investigation on Caesalpinia crista afforded two new diterpenoids, 6beta-cinnamoyloxy-7beta-acetoxyvouacapen-5alpha-ol and 6beta,7beta-dibenzoyloxyvouacapen-5alpha-ol and on Caesalpiniapulcherrima another new diterpenoid, 12-demethyl neocaesalpin F along with several known constituents. The structures of the new compounds were settled from their 1D and 2D NMR spectral data. The cytotoxicity of these compounds was measured on two different cancer cell lines.

The first stereoselective total synthesis of a new antitumour and anti-inflammatory neolignan, surinamensinol A

The stereoselective total synthesis of an antitumour and anti-inflammatory 8-O-4′-neolignan, surinamensinol A has been accomplished starting from two aldehydes, 3,4,5-trimethoxy benzaldehyde and vanillin. The key steps involve an asymmetric reduction using a chiral oxazaborolidine complex, a Sharpless asymmetric dihydroxyllation and a Mitsunobu reaction. This is the first report of the total synthesis of surinamensinol A.

A new strategy for the synthesis of crucigasterin A, and cytotoxic activity of this compound and its related analogues ☆

Stereoselective total synthesis of bioactive marine natural product crucigasterin A has been accomplished from commercially available and inexpensive L-(-)-malic acid as a starting material. Julia olefination and chelation controlled Grignard additions are the key steps involved in the present synthesis. Cytotoxic properties of crucigasterin A and its related analogues crucigasterins B and D have been evaluated. Crucigasterin A showed promising activities against both the human cervical cancer cell line and human breast adenocarcinoma cell line.