A protocol for directly accessing geminal C-4 diarylated pyrazol-5(4H)-ones via tandem C-H aryne insertion and their inceptive neurobiological evaluation.

Geminal C-4 diarylation of substituted pyrazol-5(4H)-ones with in situ generated arynes as the aryl source has been achieved in a one-flask operation. All the newly accessed C4-gem-diarylated pyrazolone entities were found to be non-cytotoxic with varying AChE enzyme inhibitory activities and BBB permeability attributes that augur well for further advancement towards CNS therapeutics for untreatable disorders.

An Approach to Functionally Embellished o-Alkynylbenzoates or Furan-3(2H)-ones from Diynones and DMAD: Controlled Divergence and Product Selectivity.

The discovery of reaction regime controlled product diversification in a one-pot reaction between diynones and dimethyl-1,3-acetonedicarboxylate (DMAD) to selectively furnish either functionally unique pentasubstituted o-alkynylbenzoates or fully substituted furan-3(2H)-ones is delineated. The potential of these two versatile platforms to enter new utilitarian chemical space has also been explored.

Stereoselective total synthesis and structural revision of the diacetylenic diol natural products strongylodiols H and I.

The stereoselective total synthesis of strongylodiol H and I has been accomplished. The synthetic procedure comprised the stereoselective reduction of a ketone functionality in an ene-yne-one employing CBS as a catalyst and a Cadiot-Chodkiewicz coupling reaction as the key reaction steps. A common aldehyde intermediate has been used for the synthesis of both strongylodiols.

A carbohydrate approach for the formal total synthesis of (-)-aspergillide C.

An enantioselective formal total synthesis of aspergillide C is accomplished using commercially available tri-O-acetyl-D-galactal employing a Ferrier-type C-glycosylation, utilizing a Trost hydrosilylation and protodesilylation as key reactions.

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.

Diverted organic synthesis (DOS): accessing a new, natural product inspired, neurotrophically active scaffold through an intramolecular Pauson-Khand reaction.

Drawing inspiration from the impressive neurotrophic activity exhibited by the natural product paecilomycine A, we have designed a new natural product-like scaffold employing an intramolecular Pauson-Khand reaction. Several compounds based on the new designer scaffold exhibited promising neurotrophic activity and are worthy of further biological evaluation. Our findings also highlight the importance of a DOS strategy in creating useful therapeutical leads.

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.

Spiroannulation of Oxindoles via Aryne and Alkyne Incorporation: Substituent-Diverted, Transition-Metal-Free, One-Pot Access to Spirooxindoles.

A "product control via substrate design" strategy has been conceptualized and implemented to harness the potential of aryne and activated alkyne insertions into oxindoles to readily and efficiently furnish pharmacophoric indano- and cyclopentannulated spirooxindole scaffolds in an operationally straightforward, one-pot, transition-metal-free protocol.

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.

Multiple Aryne Insertions into Oxindoles: Synthesis of Bioactive 3,3-Diarylated Oxindoles and Dibenzo[b,e]azepin-6-ones.

An aryne insertion cascade reaction on oxindoles has been observed and constitutes a convenient "one pot" preparation of bioactive di- and triarylated oxindoles in good yields under mild conditions. A temperature controlled "reaction switch" enables ready access to dibenzo[b,e]azepin-6-one derivatives employing the same reaction regime. This tactic has been extended to a short synthesis of potent antiulcer agent darenzepine.

From vinyl pyranoses to carbasugars by an iron-catalyzed reaction complementary to classical Ferrier carbocyclization.

Starting from vinyl pyranoses an iron-catalyzed tandem isomerization-intramolecular aldolization reaction was developed to prepare cyclohexenone derivatives bearing substituents on the double bond, and it has been applied in a short synthesis of 4-epi-gabosines A and B, from d-glucose.

A facile and chemoselective conjugate reduction using polymethylhydrosiloxane (PMHS) and catalytic B(C6F5)3.

A highly chemoselective conjugate reduction of electron-deficient Michael acceptors, including alpha,beta-unsaturated ketones, carboxylic esters, nitriles and nitro compounds with PMHS in the presence of catalytic B(C6F5)3 is described.