Rudraraju Ramesh Raju

Synthesis, cytotoxic activity and docking studies of new 4-aza-podophyllotoxin derivatives

Abstract The synthesized nine aza-podophyllotoxin derivatives (8a–f, 10, 12and14) have been evaluated for their cytotoxicity in a panel of tumor cancer cell lines (Zr-75-1, MCF7, KB, Gurav, DWD, Colo-205, A-549 and Hop62). Among them, 8a and 8b compounds show stronger growth inhibition activity than the standard drug etoposide. Further, molecular docking simulations were carried out against human topoisomerase II, a putative target for these classes of molecules.

A concise stereoselective total synthesis of (−)-cephalosporolide D

A concise stereoselective total synthesis of eight-membered lactone (−)-cephalosporolide D has been derived from inexpensive and commercially available starting material (S)-propylene epoxide. This concise synthesis utilizes Grignard reaction, Noyori asymmetric reduction, and Yamaguchi macrolactonization as key steps.Graphical abstract

A concise stereoselective total synthesis of diplodialide C

An asymmetric total synthesis of diplodialide C has been achieved starting from commercially available homoallylic alcohol. Regioselective opening of the chiral epoxide, cross-metathesis reaction, and Yamaguchi macrolactonization were used as the key steps in this synthesis.Graphical Abstract

Synthesis of chalcone incorporated quinazoline derivatives as anticancer agents

A series of ten novel chalcone incorporated quinazoline derivatives (11a–11j) were designed and synthesized. All the synthesized compounds were evaluated for their anticancer activities against four human cancer cell lines (A549, HT-29, MCF-7 and A375). Among them, four compounds, 11f, 11g, 11i and 11j showed more potent anticancer activity than the control drug, Combretastatin – A4.

Stereoselective total synthesis of (−)-(5S,8R,13S,16R)-pyrenophorol

The total synthesis of 16-membered C2-symmetric dilactone (−)-(5S,8R,13S,16R)-pyrenophorol was accomplished starting from enantiomerically pure propylene oxide prepared by hydrolytic kinetic resolution of (±)-propylene oxide with key steps of cross-metathesis and intermolecular Mitsunobu cyclization for the construction of macrolactone.Graphical abstract

Stereoselective total synthesis of verbalactone

Abstract A simple and efficient route for the stereoselective total synthesis of verbalactone from commercially available inexpensive starting material d-mannitol using Barbier allylation, α-aminoxylation, and Yamaguchi macrolactonization as key steps is reported.Graphical Abstract

Stereoselective synthesis of (−)-tetrahydropyrenophorol

A simple and efficient synthesis of macrocyclic dilactone tetrahydropyrenophorol has been accomplished from inexpensive and commercially available starting materials. This concise synthesis utilizes regioselective ring opening of epoxide, asymmetric dihydroxylation, and Mitsunobu reaction for the construction of the macrolactone.Graphical abstract

An alternative stereoselective total synthesis of (-)-pyrenophorol

Abstract The total synthesis of 16-membered C2–Symmetric dilactone (-)-Pyrenophorol was accomplished starting from commercially available (S)-epoxide prepared by hydrolytic kinetic resolution of (±) – epoxide with key steps of Grignard reaction, Swern oxidation, Wittig reaction and cyclization was achieved by intermolecular Mitsunobu cyclization. The synthesis of (-)-Pyrenophorol accomplished from cheaply available starting material, easily work-up procedures and reduction of cost in industrial process were major advantages of this route.