Pentafluorophenyl Esters of Dicarboxylic Acids

Di- and half-esters of various dicarboxylic acids and dicarboxylic monoamides with pentafluorophenol were prepared. Their syntheses, properties, and spectroscopic data are reported.     

Substituted Amides and Hydrazides of Dicarboxylic Acids. Part 11.1 Synthesis and Pharmacological Activity of a Series of Pyridylamides of Dicarboxylic Acids

Pharmaceutical Chemistry Journal -     

Substituted Amides and Hydrazides of Dicarboxylic Acids. Part 18. Synthesis and Hypertensive Activity of 3(6)-Methyl-2-pyridylamides of Some Dicarboxylic Acids

Pharmaceutical Chemistry Journal -     

Microwave-assisted Heterocyclic Dicarboxylic Acids as Potential Antifungal and Antibacterial Drugs

A series of new dicarboxylic acid derivatives of 1,3,4-thiadiazines, 1,4-benzopiperizines, 1,4-thiazines, 1,3-thiazoles, 1,3-oxazoles and 1,3-imidazoles have been synthesized in 80-87% yield by the environmentally benign microwave induced technique involving the cyclocondensation of 2,3-dibromosuccinic acid with 2-aminothiophenol, o-phenylene diamine, 1,2,4-triazole, amidinothiocarbamide, amidinocarbamide and guanidine hydrochloride. The structures of all newly synthesized compounds have been established on the basis of analytical and spectral data. Evaluation of antibacterial and antifungal activity showed that almost all compounds exhibited better results than reference drugs thus they could be promising candidates for novel drugs.     

Substituted Amides and Hydrazides of Dicarboxylic Acids. Part 9. Pharmacological Activity of the Products of Interaction of 2-Aminopyridines and 2-Aminopyrimidine with Dicarboxylic Acid Anhydrides

Pharmaceutical Chemistry Journal -     

Substituted Amides and Hydrazides of Dicarboxylic Acids. Part 15. Synthesis and Hypoglycemic Activity of Some Amides and Acylhydrazides of Tetrachlorophthalic Acid

Pharmaceutical Chemistry Journal -     

Substituted Amides and Hydrazides of Dicarboxylic Acids. Part 16. Synthesis and Antibacterial Activity of Some Amides and Acylhydrazides of Succinic Acid

Pharmaceutical Chemistry Journal -     

Structural Characterization and Pharmaceutical Properties of Three Novel Cocrystals of Ethenzamide With Aliphatic Dicarboxylic Acids

Ethenzamide (ET) was screened in cocrystallization experiments with pharmaceutically acceptable coformer molecules to discover materials of improved physicochemical properties, that is, higher solubility and better stability. Three novel cocrystals of ET with glutaric, malonic, and maleic acids were obtained by neat grinding and slow evaporation from solution. The purpose of the study was to notice the changes in the geometry and interactions of ET molecule in crystalline phase introduced by different acid and relate them to physicochemical properties of pure ET. Therefore, the crystal structure of the cocrystals was determined by single crystal X-ray diffraction analysis. The powder samples were characterized by differential scanning calorimetry, Fourier-transform infrared spectroscopy, and ¹³C and ¹⁵N solid-state nuclear magnetic resonance spectroscopy. Spectroscopic studies were supported by gauge including projector augmented wave calculations of chemical shielding constants. The high stability of cocrystals during direct compression was proved. The solubility in simulated gastric fluids for studied cocrystals appeared to be approximately 1.6 times-fold higher than ET. The dissolution rates of all ET cocrystals were not faster than the pure drug, but after 240 min, more drugs were released.     

Substituted Amides and Hydrazides of Dicarboxylic Acids. Part 10. Synthesis and Pharmacological Activity of Substituted Amides and Hydrazides of Succinic Acid

Pharmaceutical Chemistry Journal -     

Substituted Amides and Hydrazides of Dicarboxylic Acids. Part 13. Synthesis and Hypoglycemic Activity of Some Substituted Amides and Acylhydrazides of Phthalic Acid

Pharmaceutical Chemistry Journal -     

Substituted Amides and Hydrazides of Dicarboxylic Acids. Part 17. Synthesis and Antibacterial and Anticonvulsant Activity of Some Amides and Acylhydrazides of Phthalic Acid

Pharmaceutical Chemistry Journal -     

Substituted Amides and Hydrazides of Dicarboxylic Acids. Part 12. Synthesis and Hypoglycemic and Hypertensive Activity of Some Pyridylamides and Acylhydrazides of Maleic and Citraconic Acid

Pharmaceutical Chemistry Journal -     

Molecular Complexes of Alprazolam with Carboxylic Acids,Boric Acid,Boronic Acids,and Phenols. Evaluation of Supramolecular Heterosynthons Mediated by a Triazole Ring

A series of molecular complexes, both co-crystals and salts, of a triazole drug—alprazolam—with carboxylic acids, boric acid, boronic acids, and phenols have been analyzed with respect to heterosynthons present in the crystal structures. In all cases, the triazole ring behaves as an efficient hydrogen bond acceptor with the acidic coformers. The hydrogen bond patterns exhibited with aromatic carboxylic acids were found to depend on the nature and position of the substituents. Being a strong acid, 2,6-dihydroxybenzoic acid forms a salt with alprazolam. With aliphatic dicarboxylic acids alprazolam forms hydrates and the water molecules play a central role in synthon formation and crystal packing. The triazole ring makes two distinct heterosynthons in the molecular complex with boric acid. Boronic acids and phenols form consistent hydrogen bond patterns, and these are seemingly independent of the substitutional effects. Boronic acids form noncentrosymmetric cyclic synthons, while phenols form O–H?N hydrogen bonds with the triazole ring. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99:3743–3753, 2010     

Preparation and Physiochemical Analysis of Novel Ciprofloxacin / Dicarboxylic Acid Salts

The crystal structures of four novel dicarboxylic acid salts of ciprofloxacin (CFX) with modified physicochemical properties, prepared by mechanochemical synthesis and solvent crystallization, are reported. A series of dicarboxylic acids of increasing molecular weight was chosen, predicted to interact via a carboxylic acid:secondary amine synthon. These were succinic (SA), glutaric (GA), adipic (AA) and pimelic (PA) acids (4, 5, 6, 7 carbon atoms respectively). Characterized by single crystal and powder X-ray diffraction, Fourier-Transform Infrared Spectroscopy, thermogravimetric analysis, differential scanning calorimetry, scanning electron microscopy and aqueous solubility measurements, these salts showed distinct physicochemical properties relative to ciprofloxacin base. Searches of the Cambridge Structural Database (CSD) confirmed CFX-SA, CFX-GA, CFX-AA and CFX-PA to be novel crystal structures. Furthermore, the GA salt has substantially higher solubility than the widely available hydrochloride monohydrate salt (CFX-HCl·H₂O). CFX-SA, CFX-GA and CFX-AA showed minimum inhibitory concentration (MIC) of 0.008 g/L and CFX-PA showed MIC of 0.004 g/L. The prepared CFX salts retained antibacterial activity exhibiting equivalent antimicrobial activity to CFX-HCl·H₂O. These salts have positive implications for increasing the application of CFX beyond conventional oral formulations and highlight mechanochemical activation as suitable production method.     

藻类脂肪酸分离提纯及检测

报道了藻类脂肪酸用索氏提取器提取脂肪，甲酯化后用气相色谱仪测定的方法，从单细胞藻类中提取脂肪酸必须破细胞壁后再用乙醚浸泡，提取的时间要达12h以上，大型藻类不用破壁，室温下用乙醚浸泡24h，再用索氏法提取5h左右即可，脂溶性色素含量较高的样品，用乙醚提取的脂肪要在检测之前用活性炭和硅藻土进行脱色，两种物质的量要适宜，否则将影响脂肪酸的含量，硅胶G－CMC混合薄层层析（正己烷，乙酸乙酯85：15为展层剂，10％磷钼酸乙醇液为显色剂），是快速检测脂肪酸的方法，计算脂肪酸的含量时，仅能计算加入石油醚和苯的上层体积，因为下层不含有脂肪酸。     

Dithranol,Singlet Oxygen and Unsaturated Fatty Acids

Chemically or photochemically generated ¹O₂ (¹Δg O₂) transforms the anion of dithranol (1) into chrysazine (2) , probably via an endo-peroxide. Under basic conditions, ³O₂ converts 1 to the bisanthrone 3 and to dithranol brown. The anion of dithranol is a photosensitizer. ¹O₂ was trapped by 2,3-dimethyl-2-butene and by methyl oleate which was converted to the C-9- and C-10-hydroperoxides. From this point of view interference of the antipsoriatic dithranol with the metabolism of arachidonic acid appears reasonable.