Design, Synthesis, and Biological Activity of New N-(Phenylmethyl)-benzoxazol-2-thiones as Macrophage Migration Inhibitory Factor (MIF) Antagonists: Efficacies in Experimental Pulmonary Hypertension
摘要:
Macrophage migration inhibitory factor (MIF) is a key pleiotropic mediator and a promising therapeutic target in cancer as well as in several inflammatory and cardiovascular diseases including pulmonary arterial hypertension (PAH). Here, a novel series of N-(phenylmethyl)-benzoxazol-2-thiones 5-32 designed to target the MIF tautomerase active site was synthesized and evaluated for its effects on cell survival. Investigation of structure-activity relationship (SAR) particularly at the 5-position of the benzoxazole core led to the identification of 31 that potently inhibits cell survival in DU-145 prostate cancer cells and pulmonary endothelial cells derived from patients with idiopathic PAH (iPAH-ECs), two cell lines for which survival is MIF-dependent. Molecular docking studies helped to interpret initial SAR related to MIF tautomerase inhibition and propose preferred binding mode for 31 within the MIF tautomerase active site. Interestingly, daily treatment with 31 started 2 weeks after a subcutaneous monocrotaline injection regressed established pulmonary hypertension in rats.
Enantioselective Strecker and Allylation Reactions with Aldimines Catalyzed by Chiral Oxazaborolidinium Ions
作者:Ki-Tae Kang、Sang Hyun Park、Do Hyun Ryu
DOI:10.1021/acs.orglett.9b02280
日期:2019.9.6
Chiral oxazaborolidiniumion (COBI)-catalyzed enantioselective nucleophilic addition reactions of aldimines using tributyltin cyanide and allyltributylstannane have been developed. Various α-aminonitriles and homoallylic amines were synthesized in high yield (up to 98%) with high to excellent enantioselectivity (up to 99% ee). A rational mechanistic model for the complex of COBI and aldimine is provided
Synthesis of 2-arylbenzoxazoles via DDQ promoted oxidative cyclization of phenolic Schiff bases—a solution-phase strategy for library synthesis
作者:Junbiao Chang、Kang Zhao、Shifeng Pan
DOI:10.1016/s0040-4039(01)02302-4
日期:2002.2
The Schiff base derived from the condensation of o-aminophenol with benzaldehydes was induced to undergo oxidative cyclization in the presence of DDQ. The resulting 2-arylbenzoxazoles were separated from the reduced DDQ byproduct by treatment of reaction mixture with a strongly basic ion-exchange resin. The applicability of this chemistry to spatially separate library synthesis is demonstrated by the