A series of 2-substituted methyl 2,3-dihydroimidazo[1,2-c]quinazolin-5(6H)-ones (4), 3-substituted methyl 2,3-dihydroimidazo[1,2-c]quinazolin-5(6H)-ones (5), 3-substituted methyl 2,3-dihydro-5H-thi...

Studies on quinazolines and 1,2,4-benzothiadiazine 1,1-dioxides. 8.1, 2 synthesis and pharmacological evaluation of tricyclic fused quinazolines and 1,2,4-benzothiadiazine 1,1-dioxides as potential alpha1-adrenoceptor antagonists.

The aim of this review is to present reactions of carbon disulfide with N-nucleophiles which form nitrogen-carbon bonds. Compounds with an amino or imino group react, in the presence of a base, with carbon disulfide to give dithiocarbamates. They can be converted to esters on treatment with an alkylation reagent. Acidification affords dithiocarbamic acids. Dithiocarbazates are formed on treatment of hydrazines with carbon disulfide. A lot of dithiocarboxylation products are valuable building blocks for heterocycles.

Reactions of carbon disulfide with N-nucleophiles

The literature data concerning the methods for preparing imidazole-2-thiones and their benzo analogs have been systematized, and the structure, physico-chemical properties and chemical conversions of these compounds have been considered. The methods for the synthesis of imidazole-2-thiones are classified according to reaction types including cyclization, reactions of halo- and oxoimidazole derivatives with sulfur-containing nucleophiles, and direct insertion of sulfur into position 2 of the imidazole ring. The structure of imidazole-2-thiones is discussed in terms of quantum-chemical calculations, X-ray diffraction data, dipole moments, UV, and IR as well as 1H and 15N NMR spectroscopy. Much attention has been given to nucleophilic addition of imidazole-2-thiones to acetylene and its derivatives as well as to alkenes with an activated double bond. The reactions of imidazole-2-thiones as nucleophilic agents, including alkylation, acylation, and interaction with carbonyl halides are discussed. Some...

Imidazole-2-Thiones: Synthesis, Structure, Properties

Die kondensierten 4(3H)-Chinazolinon-Derivate 4a–e wurden aus 2-Thioxo-1H,3H-chinazolin-4-on (1) durch Behandlung mit den Halogeniden 2a–e dargestellt. Eine vorlaufige pharmakologische Prufung zeigte, das die Verbindungen 4b–4d nach i. v. Zufuhr von 5–10 mg/kg an anasthesierte Ratten sehr gute antihypertensive Aktivitat aufweisen.



Synthesis and Antihypertensive Activity of Some Quinazolinone Derivatives



The fused 4(3H)-quinazolinone derivatives 4a–e were synthesized by treating 2-thioxo-1H,3H-quinazolin-4-one (1) with the halides 2a–e. A preliminary pharmacological evaluation revealed that the compounds 4b–4d act as antihypertensives in anesthetized rats at i.v. doses of 5–10 mg/kg.

Synthese und antihypertensive Aktivität einiger Chinazolinon-Derivate

http://www.kau.edu.sa/files/0056396/researches/57723_27923.pdf

2-Amino-4-thiazolidinones: synthesis and reactions

Darstellung von 2‐Methoxycarbomethyliden‐1H‐perimido[2,1‐b] 3‐thiazolidinon

Synthese einiger 2-Methylbenzimidazo[2,1-b]-2,3-dihydro-1,3-thiazin-4-one

Treatment of aliphatic 1,2-, 1,3- or aromatic o-diamine with carbon disulfide provided the corresponding cyclic pseudothioureas (IIb-j). Heating thiourea (IIa) or these compounds with dimethyl or diethyl acetylenedicarboxylate (IIIa, b) in ethanol resulted a nucleophilic addition of the sulfhydryl group to the C≡C bond accompanied with a ring-closure condensation. Thus a series of alkoxycarbo-methylidene derivatives of 2-imino-4-thiazolidinone (IVa), imidazolo-, benzimidazo-and tetrahydropyrimido (2, 1-b)-3-thiazolidinones (IVb-k) was produced. An orientating experiment of saponifying the ester function of these compounds has also been carried out.

Bi-Jane Shih

Papers

Darstellung von 2‐Methoxycarbomethyliden‐1H‐perimido[2,1‐b] 3‐thiazolidinon

Synthese einiger 2-Methylbenzimidazo[2,1-b]-2,3-dihydro-1,3-thiazin-4-one

Reactions of Cyclic Pseudothioureas with Acetylenedicarboxylates