P. Srihari

Solvent free synthesis of 1,5-disubstituted tetrazoles derived from Baylis Hillman acetates as potential TNF-α inhibitors

Solvent free multicomponent reaction of Baylis Hillman acetate, TMS azide and arylnitrile to produce 1,5-disubstituted tetrazole is described. Some of these tetrazoles are found to be potential TNF-alpha inhibitors.

Scandium triflate-catalyzed 1,3-dipolar cycloaddition of aziridines with alkenes ☆

Abstract Phenyl aziridines undergo 1,3-dipolar cycloaddition efficiently with olefins such as cyclic enol ethers and allyltrimethylsilane in the presence of a catalytic amount of Sc(OTf)3 at ambient temperature to afford the corresponding pyrrolidine derivatives in high yields with high regioselectivity.

aza-Flavanones as potent cross-species microRNA inhibitors that arrest cell cycle

aza-Flavanones have been identified as a new class of selective microRNA inhibitors. These compounds were found to arrest cell cycle via a novel cross species microRNA-dependent regulatory pathway interpreting an unexpected link between cell cycle arrest and microRNA mediated control in cancer.

Formation of Substituted Tetrahydropyrans through Oxetane Ring Opening: Application to the Synthesis of C1–C17 Fragment of Salinomycin

The stereoselective synthesis of C1-C17 fragment of salinomycin is achieved. The strategy employs a desymmetrization approach and utilizes an intramolecular oxetane opening reaction with O-nucleophile to result in the tetrahydropyran skeleton as the key step.

Versatile Route to Benzoannulated Medium-Ring Carbocycles via Aryne Insertion into Cyclic 1,3-Diketones: Application to a Synthesis of Radermachol

A general approach involving the insertion of in situ generated aryne into the C-C bond of cyclic 1,3-diketones for rapidly assembling functionalized benzo-fused medium ring carbocycles is delineated. The efficacy of the methodology has been demonstrated through a concise total synthesis of pentacyclic natural product radermachol.

PMA‐SiO2: A Heterogenous Catalyst for O‐, S‐, and N‐Nucleophilic Substitution Reactions of Aryl Propargyl Alcohols

Abstract Aryl‐propargylic alcohols undergo O‐, S‐, and N‐nucleophilic substitution reactions in the presence of a catalytic amount of PMA‐SiO2.

New and practical synthesis of 1,4-dihydrobenzopyrano-pyrazoles

A new method for the synthesis of 1,4-dihydrobenzopyranopyrazoles using bromovinyl hydrazones has been described involving a [3+2] intramolecular cycloaddition.

First Concise Total Synthesis of 5‐Epi‐prelactone B

First short total synthesis of 5-epi-prelactone B has been achieved involving Sharpless asymmetric epoxidation and intramolecular hydride transfer reaction for formation of the aldol product by nonaldol chemistry as the key steps.

Total synthesis of (+/-)-elegansidiol, (+/-)-farnesiferol B, and (+/-)-farnesiferol D.

The racemic total synthesis of elegansidiol, farnesiferol B, and farnesiferol D has been obtained following a Diels-Alder approach. Gillman addition, cross metathesis reaction are the other key steps involved in the target synthesis.

PMA-SiO2 catalyzed synthesis of indolo[2,3-c]quinolines as potent anti cancer agents.

PMA-SiO2 catalyzed Pictet-Spengler reaction of aryl amine linked to C-3 of the indole and the aryl aldehydes was achieved. In the series of the synthesized compounds, 6b, 10b and 12b were found to be cytotoxic against prostate, lung, breast and cervical cancer cell lines selectively with no significant effect on the growth of the control fibroblast cell line NIH3T3. Further determining their cytotoxic potential we found that 10b and 12b show cell cycle arrest in DU145 prostate cancer cells indicating a role in cell cycle progression. Both the molecules showed effect on decreased phosphorylation of NF-κB on serine 536 residue which is strongly implicated in many different types of cancers. Taken together, the series of indoloquinolines elicit potent anti-cancer potential providing a mean for developing novel indoloquinoline based anti-cancer agents.