The results of electronic structure studies aimed at determining accurate enthalpies of formation and proton affinities for a comprehensive set of C4H7N and C3H3ON compounds are reported. The calculated thermodynamic values are rationalized in terms of the nitrogen functionality and the influence of unsaturated C–C bonding environments. Using these results, it is proposed that a previously unid...

Several cardiotonic steroids have been modified by reduction of the unsaturated lactone and their interactions with the sodium- and potassium-activated ATPase ((Na+ + K+)-ATPase) have been investigated. Reduction of the unsaturated lactone results in a decrease in binding affinity due primarily to an increase in the dissociation rate constant concomitant with a decrease in the activation free e...

A versatile and high-yielding indium trichloride mediated cyclization reaction of silylated homoallylic alcohols, thiols, or amines with aldehydes or epoxides is described as a rapid route to a range of unsaturated heterocycles. The excellent diastereoselectivity observed offers a method of wide scope and generality.

The increased activity of phase-II-detoxification enzymes, such as quinone reductase (QR) and glutation S-transferase (GST), correlates with protection against chemically induced carcinogenesis. Herein we studied 11 different chemotypes, pyrazole, 1,2,4-oxadiazole, 1,2,5-oxadiazole, 1,2,3-thiadiazole, 1,2,4-thiazole, 1,3,4-oxathiazole, thienyl hydrazone, α,β-unsaturated-oxime, α,β-unsaturated-N...

a,b-Unsaturated carbonyl compounds are basic building blocks in organic synthesis. Lewis acid catalysts bearing chiral ligands have traditionally been used for the asymmetric catalytic activation of this class of molecules as Michael acceptors. Indeed, Lewis acid catalysis continues to be a powerful approach in which innovative solutions are still emerging. Representative examples of chiral Lew...

A simple and efficient method for the synthesis of 1,1-diarylalkanes via the Friedel-Crafts-type alkylation reaction of electron-rich arenes with cinnamic acid ester derivatives or chalcones is reported. Iron triflate has been found to be the best catalyst for the Friedel-Crafts-type alkylation reaction with α,β-unsaturated carbonyl compounds. This reaction afforded β,β-diaryl carbonyl compound...

Electroantennograms (EAGs) were recorded from unmated, laboratory-reared, male and female oriental fruit flies, Dacus dorsalis, in response to a range of between C~ and Cl2 carbon chain-length saturated and unaturated aliphatic alcohols and aldehydes, most all of which are known host-plant volatiles. Only two of the 35 compounds tested elicited significantly larger EAGs from female than male an...

Plant endophytic microorganisms represent a largely untapped resource for new bioactive natural products. Eight polyketide natural products were isolated from a mangrove endophytic fungus Phomosis sp. A818. The structural elucidation of these compounds revealed that they share a distinct feature in their chemical structures, an oxygen-bridged cyclooctadiene core skeleton. The study on their str...

Efficient one-pot methods for the synthesis of variously functionalised conjugated nitro alkenes have been reported. Despite the utility in different fields of these compounds, only a few multi-step syntheses have been reported in the literature, giving the target compounds in low overall yields. α-Nitro acrylates or cinnamates, α-nitro α,β-unsaturated ketones and, most importantly, aromatic an...