Xushun Qing

Solvent-Free DABCO-Mediated [3 + 2] Cycloadditions of Donor–Acceptor Cyclopropanes with Aldehydes: Strategy for Synthesis of Fully Substituted Furans

DABCO-mediated [3 + 2] cycloadditions of donor-acceptor cyclopropanes with aldehydes under solvent-free conditions have been developed for the preparation of fully substituted furans which are a wide range of structurally interesting and pharmacologically significant compounds. The reaction appears to be general for a variety of 1-cyanocyclopropane-1-carboxylates and aldehydes and tolerates the presence of aromatic moieties with electron-withdrawing and electron-donating substituents.

One-pot synthesis of 2,4,6-triarylpyridines from β-nitrostyrenes, substituted salicylic aldehydes and ammonium acetate

A protocol for the synthesis of 2,4,6-trisubstituted pyridines from the β-nitrostyrenes, available substituted salicylic aldehydes and ammonium acetate was developed. The present strategy features high chemoselectivity and excellent tolerance for a broad range of functional groups, in which the β-nitrostyrenes generated from aldehydes and nitromethane, substituted salicylic aldehydes and ammonium acetate were respectively employed as simple and easily available substrates. This efficient method provides fast access to a variety of structurally diverse pyridine derivatives. The structures of two typical products were confirmed by X-ray crystallography.

Brönsted acid-mediated annulations of 1-cyanocyclopropane-1-carboxylates with arylhydrazines: efficient strategy for the synthesis of 1,3,5-trisubstituted pyrazoles

1-Cyanocyclopropane-1-carboxylates are reacted with arylhydrazines to afford 1,3,5-trisubstituted pyrazoles under the influence of a Bronsted acid. Formally, this transformation can be regarded as an annulation of three-membered rings with α-carbonyl and hydrazines. This newly efficient method provides access to a variety of structurally diverse pyrazole derivatives. The structures of five typical products were confirmed by X-ray crystallography.

Selective hydrolysis of 1-cyanocyclopropane-1-carboxylates: concise preparation of 1-carbamoylcyclopropane-1-carboxylates

An efficient and straightforward method has been developed for the preparation of 1-carbamoylcyclopropane-1-carboxylate derivatives via selective hydrolysis of 1-cyanocyclopropane-1-carboxylates by using hydroxylamine and sodium acetate system strategy. The structure of 1-carbamoylcyclopropane-1-carboxylate 2a was further confirmed by X-ray single crystal analysis.

Regioselective construction of 1,3-diaryl tetrahydroindazolones via the three-component reaction of 1,3-cyclohexanediones, β-nitrostyrenes and arylhydrazines

1,5,6,7-Tetrahydro-4H-indazol-4-one derivatives were successfully synthesized using a one-pot three-component system that combines substituted β-nitrostyrenes, 1,3-cyclohexanediones and phenylhydrazines. This reaction involves a highly efficient domino sequence consisting of the aza-Michael reaction, intramolecular O-nucleophilic addition, nucleophilic addition, and ring opening of furan as the key unit steps. Notably, the highly regioselective construction of the tetrahydro-4H-indazolone moiety and the introduction of functionalized aromatic rings were achieved.

Synthesis and biological evaluation of 3β-androsta-5,8(14),15-trien-17-one derivatives as potential anticancer agents

A novel and operationally simple method for highly efficient synthesis of promising anti-cancer 3β-hydroxy-16-arylandrosta-5,8(14),15-trien-17-ones was reported. Compounds were tested for their cytotoxic activities against A549, SKOV3, MKN-45 and MDA-MB-435 cancer cell lines. The preliminary results showed that compounds 5e, g were the most active especially against cancer cell lines tested.