Synthesis and anti-HBV activity of S-substituted 7-mercapto-4-methylcoumarin analogs

Twelve S-substituted 7-mercapto-4-methylcoumarin analogs were synthesized and evaluated for the inhibition to HBV in HepG2 2.2.1.5 cell. Among them, ten compounds exhibited potent inhibition to HBsAg and/or HBeAg with the IC50 values of sub μmol/L level. The ICso of anti-HBsAg activities of 5c and 5j reached 0.01 μmol/L respectively which were 16 fold more potent than that of 3TC. Compounds 3, 5e, 5g, 5h and 5i showed admirable inhibitory activity to both HBsAg and HBeAg. The bioassay results indicated the S-substituted 7-mercapto-4-methylcoumarin analogs merit attention as novel anti-HBV agents.

7-氨基-4-甲基香豆素的合成

以间氨基苯酚和乙酰乙酸乙酯为原料，在浓硫酸存在下，进行Ｐｅｃｈｍａｎｎ缩合反应，生成荧光物质———７氨基４甲基香豆素，并采用正交设计法，进行最佳工艺条件优选，总得率超过文献产率。

Synthesis and Crystal Structure of Ethyl 2-(6-(1,3-Dioxo-4,5,6,7-tetrahydro-1H-isoindol-2(3H)-yl)-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4(3H)-yl) Butanoate

The title compound ethyl 2-（6-（1,3-dioxo-4,5,6,7-tetrahydro-lH-isoindol-2（3H）- yl）-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4（3H）-yl） butanoate 3 was synthesized by the reaction of ethyl 2-（6-amino-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4（3H）-yl） butanoate with 4,5,6,7- tetraydrophthalic anhydride, and its structure was determined by X-ray single-crystal diffraction. The crystal belongs to the monoclinic system, space group P2 1/n with a = 9.3469（2）, b = 16.7715（5）, c = 13.7153（4） A, β= 104.9680（10）°, μ = 0.107 mm^-1, Mr = 430.42, V= 2077.08（10） ,A3, Z= 4, Dc = 1.376 g/cm3, F（000） = 904, T= 296（2） K, R = 0.0508 and wR = 0.1478.

Preparation of 2-amino-5,7-dimethoxy-4-aryl/alkyl-4H-chromene-3-carbonitriles using Na_2O-Al_2O_3-P_2O_5 glass–ceramic system

A highly efficient and environmentally benign protocol for the synthesis of 2-amino-5,7-dimethoxy-4- aryl/alkyl-4H-chromene-3-carbonitrile derivatives by one-pot three-component coupling reacting of aromatic aldehydes, malononitrile and 3,5-dimethoxy phenol under reflux condition has been developed in aqueous EtOH media using Na2O-Al2O3-P2O5 glass-ceramic system.

香豆素类荧光底物的合成及其在微生物检测中的应用进展

香豆素类荧光底物主要是由作为荧光团的羟基香豆素和7-氨基-4-甲基香豆素或者它们的取代物的各类衍生物,包括糖苷类、羧酸酯类、磷酸酯类、肽类等。本文介绍了这些底物的合成方法。荧光团一般通过Pechmann缩合法合成,然后再与乙酰溴代糖、酰氯、亚磷酸酯、叔丁氧基保护的氨基酸等缩合生成相应的荧光底物,像4-甲基伞形酮基-β-D-吡喃半乳糖苷、4-甲基伞形酮辛酸酯和L-丙氨酰-7-氨基-4-甲基伞形酮等。将荧光底物加入到培养基中,可以实现对微生物的快速检测。荧光底物应用于微生物检测的依据是特异性酶反应,不同的荧光底物对应的酶和所检测的微生物不同。当单一底物不能有效检测和鉴定目标微生物时,采用复合底物能明显提高检测效果。此外,本文还指出了现有荧光底物存在的缺点,并对未来发展进行了展望。

Two new coumarin glucosides biosynthesized by transgenic hairy roots of Polygonum multiflorum

The glycosylation of hydroxylcoumarin was investigated by using suspension cultures of hairy roots of Polygonum multiflorum. Two new coumarin glucosides （3 and 4） were biosysthesized by regioselectively glycosylation of corresponding substrates （1 and 2） in the system. The structures of two products were identified as 7-hydroxy-4-methylcoumarin 5-O-β-D-glucopyranoside and 7- hydroxy-3,4-dimethylcoumarin 5-O-β-D-glucopyranoside on the ground of chemical and spectroscopic methods, respectively. 2007 Rong Min Yu. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

An efficient regioselective sonochemical synthesis of novel 4-aryl-3-methyl-4,5-dihydro-1H-pyrazolo[3,4-b]pyridin-6(7H)-ones

An efficient ultrasound-assisted preparation of a series of novel 4-aryl-3-methyl-4,5-dihydro-l//-pyrazolo[34-b]pyridin-6（7H）ones via the reaction of 5-amino-3-methyl-1H-pyrazole,Meldrum＇s acid and various arylaldehydes using one-pot three-component approach is described.This rapid method produced the products in short reaction times（3-4 min） and excellent yields（87-95%）.

A New Chemiluminescent Triazine Reagent

A new chemiluminescent reagent 7-(4,6-dichloro-1,3,5-triazinylamino)-4-methylcoumarin-4-methylcoumarin (DTMC) was synthesized by linking 7-amino-4-methylcoumarin to cyanuric chloride at 0-5 degreesC, and with it a novel chemiluminescence method was developed for the determination of hydrogen peroxide. The selectivity of this method is high, and most of the transition metal ions have no effect on the determination of H2O2.

Improved microwave-assisted catalyst-free synthesis of9-aryl-5,9-dihydropyrimido[4,5-d][1,2,4]triazolo[1,5-a]pyrimidine-6,8(4H,7H)-dione derivatives

Agreen regioselective synthesis of some new and known 9-aryl-5,9-dihydropyrimido[4,5-d][l,2,4]triazolo[1,5-a]pyrimidine-6,8（4H,7H）-diones has been described via the microwave-assisted one-pot reaction of 3-amino-1H-1,2,4-triazoles,aromatic aldehydes and barbituric acids under solvent- and catalyst-free conditions.This operationally simple procedure is less laborious and provides a better scope than previously reported procedures.

Synthesis, Characterization, Thermal Stability and Antibacterial Activity of Coumarin Based Methacrylate Copolymers

Monomer of 7-methacryloyloxy-4-methylcoumarin （MAOMC） was synthesized and characterized by FTIR, 1H-NMR and 13C-NMR spectroscopy. Copolymers of MAOMC with butoxyethylmethacrylate （BOEMA） at different feed compositions were prepared by free radical solution polymerization at （70 ± 1） ℃ in ethylmethylketonc （EMK） using benzyl peroxide （BPO） as an initiator. The copolymers were characterized by FTIR and IH-NMR spectroscopy. Thermogravimetric analysis （TGA） and differential scanning calorimetry （DSC） of the copolymers showed moderate thermal stability and higher Tg values. Gel permeation chromatography （GPC） was used to find out the molecular weights of the different copolymers. Antibacterial activities of the copolymers were also investigated against the selected pathogenic bacteria＇s. The antibacterial activity of the copolymer increases as the MAOMC content increases in the copolymer. This shows that coumarin moiety plays a very important role in the antibacterial activity.