Synthesis and Reactions of Some 1-Thiapyran-4-One Derivatives

The preparation of some 3,5-diarylidene-1-thipyran-4-one derivatives (Ia-e) was described. Oxidation of Ia, b and Ie with hydrogen peroxide gave the corresponding dioxides (IIa-c). Reaction of the 1-thiapyran-4-one derivatives with bromine, Grignard reagents, and amines were studied. Structural assignments are supported by spectral (UV, IR, and ¹HNMR) data.     

Some Cyclization Reactions with 2-Ethoxycarbonylmethylidene-4,5-Dihydro-4-Thiazolinone

2-Ethoxycarbonylmethylidine-4,5-dihydro-4-thiazolinone (1) was condensed with bis aromatic aldehydes such as terephthalaldehyde or 4,4′-bisformyl-diphenylether (2a,b) (2:1 molar ratio) and furnished bis-4-thiaozlidinones (3a,b). The reaction of (3a,b) with malononitrile and aromatic aldehydes (1:2:2 molar ratio) gave bis thiazolopyridines (4a–d). Bis-(thiazolopyridine) derivative (6) was obtained by reaction of 4-thiaozlinone (5c) with bis aldehyde (2b) in refluxing ethanol containing piperidine. Cyclization of 4-thiazolinones (5a,b) with different α-cyanocinnamonitriles gave thiazolo[3,2-a]pyridines (7a–d). Compound 9 was produced via the reaction of 8 with thioglycolic acid, which reacted with p-chlorobenzaldehyde to produce 10. Compound 10 was condensed with hydrazine hydrate and afforded 11. Compounds 12 and 16a,b were produced by the reaction of 9 with isatin and α-ethoxycarbonylcinnamonitriles, respectively.     

Synthesis and Some Reactions of Coumarin‐3‐yl Crotononitrile Derivatives

Several new coumarinyl crotononitriles, 2a‐i, coumarinyl cinnamocoumarines 3a,b, 4‐amino‐3‐(substituted)‐3,4‐dihydrocoumarin 4a‐c and 9a‐c, nicotinic acid derivatives 10a,b and 4‐ethoxy‐3‐substituted‐3,4‐dihydrocoumarins 11, were synthesized from 3‐acetyl and/or 3‐benzoyl coumarin. The behavior of coumarin‐3‐yl crotononitriles 2a,b toward some electrophilic and nucleophilic reagents have been described with the aim of preparing some new heterocyclic compounds.     

Some Reactions with 3-(2-Chloro-7-Methylquinolinyl) Chalcone Derivatives

The preparation of some new 3-quinolinylchalcone derivatives was described. Their reaction with hydrazines, hydroxylamine hydrochloride, malononitrile and ethyl cyanoacetate gave the corresponding pyrazoline, isoxazoline, cyanopyridine and cyanopyridone derivatives, respectively. The biological activity of some of the products was evaluated.     

Synthesis and Some Reactions of 4-Aroyl-3-Chloro-6-p-Tolylpyridazines

4-Aroyl-3-chloro-6-p-tolylpyridazines (3a &b) were prepared by the action of phosphorous oxychloride on (2). (3a &b) react with hydrazine hydrate to give the pyrazolinopyridazines (4a &b) and with hydroxylamine hydrochloride to give the isoxazolopyridazines (7a &b), respectively. (4b) was also synthesized by the action of phosphorous oxychloride on the hydrazone (5). The reaction of (3a &b) with primary amines in boiling ethanol gives (8a-e), while their reaction with primary aromatic amines in the presence of solvent gives the Schiff's bases (9a-c).     

4-二甲胺偶氮苯磺酰氯柱前衍生高效液相色谱法测定人体尿液中肌氨酸

建立了以4-二甲胺偶氮苯磺酰氯为柱前衍生试剂的高效液相色谱法测定人体尿液中肌氨酸的含量。通过优化衍生反应的条件,确定了最佳衍生条件为:反应时间20min,反应温度75℃,衍生反应pH为9.8,衍生试剂与肌氨酸比例为4∶1。采用Agilent TC-C18柱(250×4.6mm,5μm),以pH=7.0的9mmol/L磷酸盐缓冲溶液-乙腈(60∶40,V/V)为流动相,流速1.0mL/min,检测波长465nm。结果表明,肌氨酸在0.002~4.00mmol/L范围内呈良好的线性关系,相关系数为0.9998;检测限(S/N=3)为0.70nmol/L;定量限(S/N=10)为2.33nmol/L;加标回收率为95.69%~107.79%。该方法简单、灵敏度高、稳定性好,可用于测定尿液中肌氨酸含量。     

The Synthesis and Some Reactions of N-Alkyl-4-Quinolone-3-Carboxylic Acids

A modification of the Gould-Jacobs reaction, particularly useful for the preparation of N-alkyl-4-quinolone-3-carboxylic acids, is described. Decarboxylation of these acids leads to N-alkyl-4-quinolones or, in the case of N-ethyl-benzo[h]-4-quinolone-3-carboxylic acid, to 4-ethoxy-benzo[h]quinoline. Evidence for the structure of the products is presented and the synthesis of relevant compounds is described.     

Reactions of 4-Nitroquinoline 1-Oxide with Aluminum Chloride

4-Nitroquinoline 1-oxide reacts with aluminum chloride to give 4-chloroquinoline 1-oxide. Aluminum chloride with 4-nitroquinoline 1-oxide forms a molecular complex in which it acts as electron acceptor and effective nucleophilic reagent (a source of chloride ions).     

Reactions of aldonitrones (3-imidazoline-3-oxides) with isothiocyanates

Cycloaddition of aldonitrones (derivatives of 3-imidazoline-3-oxide) to isothiocyanates depends on the N(1) substituent. Electron donating substituents facilitate cycloaddition to the C=N bond, whereas electron acceptors activate the C=S bond. Hydrolysis of adducts on the C=N bond followed by oxidation gives nitroxide radicals which are pH-sensitive spin probes.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences, 630090 Novosibirsk. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 11, pp. 2642–2647, November, 1991.     

Reactions with N-Carbonylsulfamoyl Chloride

N-Carbonylsulfamoyl chloride (NCSA) is an intermediate that can be obtained from cyanogen chloride and sulfur trioxide, and which reacts with many compounds, via electrophilic substitution, much more readily than other isocyanates. Reactions with compounds containing hydroxyl, amino, or carboxyl groups lead to N-chlorosulfonylurethanes, -ureas, and -amides, respectively. This group of products also includes the parent substance sulfamoyl chloride (amidosulfonyl chloride). The reaction of N-carbonylsulfamoyl chloride with olefins provides an easy route, not only to derivatives of β-amino acids and unsaturated carboxylic acids, but also to many β-lactams. New, very reactive sulfonylisocyanates of several types can be obtained by further reactions of primary products obtained from N-carbonylsulfamoyl chloride and by the reaction of N-carbonylsulfamoyl chloride with olefins in the presence of free-radical formers. When allowed to react with a number of compounds, NCSA undergoes loss of carbon dioxide to form products containing the grouping = N? SO₂Cl.