Synthesis and Biological Evaluation of 1, 3-Dihydroxyxanthone Mannich Base Derivatives as Potential Antitumor Agents

A novel series of Mannich bases of 1, 3-dihydroxyxanthone derivatives were designed and synthesized. The chemical structures of the compounds were characterized by IR, MS and NMR spectra. Their in vitro toxicities on six tumor cell lines including NCI-H460 (lung cancer), TCA-8113 (tongue squamous cell carcinomas), BEL-7402 (liver cancer), HepG2 (hepatocarcinoma), SGC-7901 (gastric carcinoma) and T24 (urinary bladder carcinoma) were studied through MTT assay. The results showed that most of the compounds displayed mild to good inhibitory activities on the cancer cell lines. Some preliminary structure-activity relationships were also discussed. </jats:sec

Horner-Wadsworth-Emmons reaction for the synthesis of unusual α,β-didehydroamino acids with a chiral axis

The Horner–Wadsworth–Emmons reaction of N-benzyloxycarbonyl(dimethoxyphosphinyl) glycine esters with σ-symmetric prochiral 4-substituted-cyclohexanones under basic conditions is described. This reaction gives unusual α,β-didehydroamino acids with a chiral axis in their racemic form. The methodology has been extended to the synthesis of dipeptides containing a phenylalanine residue and these unusual new α,β-didehydroamino acids at the i+2 position.This work was carried out with the financial support of Ministerio de Ciencia y Tecnología and FEDER (project PPQ2001-1834). G. S. was supported by a AECI fellowship.Peer reviewe

Horner–Wadsworth–Emmons reaction for the synthesis of unusual alpha,beta-didehydroamino acids with a chiral axis

The Horner–Wadsworth–Emmons reaction of N-benzyloxycarbonyl(dimethoxyphosphinyl) glycine esters with σ-symmetric prochiral 4-substituted-cyclohexanones under basic conditions is described. This reaction gives unusual α,β-didehydroamino acids with a chiral axis in their racemic form. The methodology has been extended to the synthesis of dipeptides containing a phenylalanine residue and these unusual new α,β-didehydroamino acids at the i+2 position.This work was carried out with the financial support of Ministerio de Ciencia y Tecnología and FEDER (project PPQ2001-1834). G. S. was supported by a AECI fellowship.Peer reviewe