A series of novel 2,3-dihydro-4H-1-benzoselenin-4-one (thio)semicarbazone derivatives were designed and synthesized by using molecular hybridization approach. All the target compounds were characterized by HRMS and NMR and evaluated in vitro antifungal activity angainst five pathogenic strains. In comparison with precursor selenochroman-4-ones, the hybrid molecules in this study showed significant
通过分子杂交的方法,设计合成了一系列新颖的2,3-二氢-4 H -1-苯并硒啉-4-酮(硫代)半碳zone酮衍生物。所有目标化合物均通过HRMS和NMR进行了表征,并针对五种病原菌株评估了其体外抗真菌活性。与前体硒代苯并二氢吡喃-4-酮相比,本研究中的杂化分子显示出显着的抗真菌活性。值得注意的是,化合物B8对除烟曲霉以外的其他菌株均表现出显着的抗真菌活性(白色念珠菌为0.25μg/ mL,新隐球菌为2μg/ mL,玉米芽孢杆菌为8μg / mL)。氟康唑敏感菌株白色念珠菌(Candida albicans)的浓度为2μg/ mL )。此外,化合物B8,B9和C2还显示出对四种氟康唑耐药菌株的最有效活性。特别地,杂合分子B8对耐氟康唑的菌株的MIC值在0.5-2μg/ mL的范围内。因此,本研究中的分子杂交方法为抗真菌药物的开发提供了新思路。
Chalcogeno Morita−Baylis−Hillman Reaction of 2-(Methylchalcogeno)phenyl Vinyl Ketones with Aldehydes, Ketones, andα-Dicarbonyl Compounds
Reactions of 2-(methylchalcogeno)phenylvinylketones 1 and 4 with aldehydes 5 were conducted in the presence of BF3·Et2O. The reaction was quenched by addition of Et3N and gave the Morita−Baylis−Hillman adducts 6−7 in good yields. When the reaction mixture of 1 with 5a was worked up with saturated aqueous NaHCO3, the sulfonium salt 8a was obtained together with 6. Ketones 10, α-diketones, and α-oxo
Synthesis and acidity constants of 13CO2H-labelled dicarboxylic acids. pKas from 13C-NMR
作者:Darren L. Holmes、David A. Lightner
DOI:10.1016/0040-4020(96)00153-6
日期:1996.4
Simple dicarboxylic acids: adipic (1), succinic (2) and malonic (3); more complex linear tetrapyrroles with two propionic acid groups: mesobiliverdin-XIIIα (4) and mesobilirubin-XIIIα (5), and a rubin analog with a gem-dimethyl at C10 (6) were prepared with 99% 13C-enrichment in their CO2H groups. Their pKavalues were determined from titrationcurves in water and in H2O-(CD3)2SO solutions: plots of
简单的二元羧酸:己二酸(1),琥珀酸(2)和丙二酸(3);制备了具有两个丙酸基团的更复杂的线性四吡咯:mesobiliverdin-XIIIα(4)和mesobilirubin-XIIIα(5),以及在C 10(6)具有宝石-二甲基的红宝石类似物,其99 C 13 CO 2 H基团。由水和H 2 O-(CD 3)2 SO溶液中的滴定曲线确定其p K a值:羧基碳13图C-NMR化学位移随p H的变化而变化。在H 2 O中具有已知p K a的二酸1-3的滴定曲线用作测定四吡咯二酸4-6的p K a s的校准标准:p K a1 = 3.9,对于4,p K a2 = 5.3 ;p K a1 = 4.2,p K a2 = 4.9(5),p K a1 = 4.7,p K a2 = 5.7H 2 O中的6。
The isoimide–imide rearrangement
作者:Kieran Brady、Anthony F. Hegarty
DOI:10.1039/p29800000121
日期:——
acid (pH <4.5) and base (pH >11.5) catalysed acyl transfer to the solvent, giving the amides (12). But at intermediate pH (6–11) rearrangement to the N-acyl form (11)(the Mumm rearrangement) alone occurs. The specific rate of this O → N acyl group migration is pH independent and shows a low solvent effect (m 0.175). Substituents attached to carbon or nitrogen have the same effect (ρ–0.84). When the migrating
(3-amino-2-hydroxy propyloxy) thiochromans of the formula ##SPC1## Wherein A is hydrogen or halogen, R.sub.1 is hydrogen or lower alkyl, and R.sub.2 is lower alkyl or cyclo lower alkyl. These compounds possess cardiovascular properties and may be used as blockers of cardiac .beta. adrenergic receptors.