Reactions of Isomeric Arylchloropyruvates and Glycidates with Hydrazines

Abstract

Reactions of arylchloropyruvic acids esters with aryl-and hetarylhydrazines give rise to pyrazolinedione hydrazones as a result of a tandem condensation of the substituted hydrazines with arylchloropyruvates. In contrast to this process in reaction with hydrazine hydrate a ready reduction unexpectedly occurs by Kizhner Wolff mechanism affording 3-hydroxydihydrocinnamic acid hydrazide as the principal product. The isomeric arylglycidate reacts along the same pattern.

Fused polycyclic nitrogen-containing heterocycles 13. Synthesis of 6-phenyl-2-phenylimino-6H-1,3,4-thiadiazine-5-carboxylic acid and its intermolecular cyclodehydration accompanied by sulfur extrusion to form dipyrazolo[1,5-a,1′,5′d]pyrazine

“…PPA is polyphosphoric acid 5 Methoxycarbonyl 6 phenyl 2 phenylimino 6H 1,3,4 thia diazine (7). A solution of chloropyruvate 1 (2.12 g, 0.01 mol) in CH 2 Cl 2 (10 mL) was added carefully dropwise to a solution of 4 phenylthiosemicarbazide (1.67 g, 0.01 mol) in CH 2 Cl 2 (30 mL) under argon at 0±2 °C.…”

Analysis of the Binding Sites on BAX and the Mechanism of BAX Activators through Extensive Molecular Dynamics Simulations

“…Their molecular structures were sketched by using the Schrodinger software (version 2017−1). 56 It should be noted that, according to the reported crystal structures of BAM7 57 and BTSA1, 58 the C�N double bond in these two molecules is in the Z configuration due to formation of an intramolecular H bond. In addition, predicted pK a values for all titratable groups on these three molecules indicate that those groups are expected to remain in their neutral form under physiological pH conditions (see Table S3 in the Supporting Information).…”

Rhodium-Catalyzed Intramolecular Transannulation Reaction of Alkynyl Thiadiazole Enabled 5,n-Fused Thiophenes

“…The precipitate was filtered off, dried in air, and recrystallized from water. To a solution of the alcohol or amine (1.0 mmol), 4dimethylaminopyridine (DMAP; 0.10 mmol, 36.7 mg), and thiadiazole-4-carboxylic acid (5; 16 1.3 mmol, 822.8 mg) in dry DCE (10 mL) at 0 °C under a nitrogen atmosphere was added N,N′dicyclohexylcarbodiimide (DCC; 1.3 mmol, 823.3 mg) in one portion. After it was stirred for 30 min at the same temperature, the reaction mixture was warmed to room temperature followed by stirring for another 3 h. Then, the reaction mixture was filtered through Celite and the mixture was washed with CH 2 Cl 2 (3 × 10 mL).…”