Synthesis of some thienopyrimidine derivatives

Thioxothienopyrimidinones, alkylthio- and arylalkylthiothienopyrimidinones, thienopyrimidinones, thienopyrimidines a thienopyrimidinedione and a thienotriazolo-pyrimidinone were prepared from 2-amino-3-carboethoxy-4,5-disubstituted thiophenes and 2-amino-3-cyano-4,5-disubstituted thiophenes via reactions with different reagents.     

Synthesis and structure of some thienopyrimidine derivatives

A series of substituted thieno[2,3-d]pyrimidines was synthesized starting from ethyl-2-amino-4-isopropylthiophene-3-carboxlate. Reaction of 2-hydrazino-5-isopropyl-thieno[2,3-d]pyrimidin-4(3H)-one and its 3-methyl analogue with different reagents afforded thieno[2,3-d]triazolo[4,3-a]pyrimidines and thieno[3,2-e]triazolo[4,3-a]pyrimidines, beside open chain derivatives. Correspondence: Atef A. Hamed, Department of Chemistry, Faculty of Science, Menoufia University, Shebin El Koam, Egypt.     

Heterocyclic compounds. VII. Synthesis of thiadiazasteroid analogs

The synthesis of a number of β-northiadiaza steroid analogs has been described. Suitable o-aminonitriles were acylated with γ-chlorobutyryl chloride. These amidonitriles were cyclized to substituted γ-lactams and subsequently to the tetracyclic products. To functionalize the “17-position” in these steroids, the intermediate γ-lactams were converted to arylidene derivatives before cyclization to the tetracyclic derivatives.     

Heterocyclic compounds XII. Quinazoline derivatives as potential antifertility agents

Several quinazoline derivatives incorporating a trans-stillbene moiety were synthesized as potential post-coital antifertility agents. Some of these compunds showed low level activity in rats.     

Condensed thienopyrimidines. II. Synthesis and gastric antisecretory activity of thiazole and polymethylene condensed thienopyrimidine derivatives

Thiazolo[3,2-a]thieno[3,2-d]-, [3,4-d]- and [2,3-d]pyrimidin-5-one derivatives (6, 11 and 16), and polymethylene condensed thieno[3,2-d]-, [3,4-d]- and [2,3-d]pyrimidin-5-one derivatives (19-21), in which the oxygen atom of the oxazolidine moiety in 3 was replaced by a sulfur atom or methylene groups, were synthesized and evaluated for gastric antisecretory activity in pylorus-ligated rats. The structure-activity relationships of these compounds are discussed.     

VI. Synthesis of Heterocyclic Analogs of γ-Aminobutyric Acid from 3,5-Dinitrobenzoic Acid

A series of 7-carboxy-3-R-1,5-dinitro-3-azabicyclo[3.3.1]non-6-enes was synthesized by reduction of 3,5-dinitrobenzoic acid with sodium borohydride followed by Mannich reaction with formaldehyde and primary amines. The mechanism of decomposition under electron impact of the 3-azabicyclo[3.3.1]nonane was established. Enthalpies of formation of compounds synthesized were calculated by semiempirical PM3 method.     

Heterocyclic nitro compounds. 25. 1-Hydroxymethyl-3-nitro-1,2,4-triazoles and their derivatives

1-Hydroxymethyl derivatives of tetrazoles were obtained by the reaction of 1,2,4-triazole and 3-nitro-5-substituted triazoles with formaldehyde in water. The hydroxy groups were replaced by chlorine, and the hydroxymethyltriazoles were acetylated and tosylated. The chloro and tosyl groups are readily replaced by iodine by the action of potassium and ammonium iodide in acetone. See [1] for communication 24. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 251–256, February, 1980.     

Heterocyclic steroids. II. Synthesis of some spiro derivatives of 7,8-diaza-11-oxasteroids

A simple, one step conversion of aldol adducts 1 derived from cyclic 1,2,3-tricarbonyl compound with 1,3-cycloalkanediones into title compounds 2 is described.     

Heterocyclic systems. VII Synthesis of 1H-pyrazolo[3,4-e]indolizine derivatives

Suitable 1-phenyl-5-(1-pyrryl)pyrazole intermediates underwent Knoevenagel or Wittig intramolecular olefination to give derivatives of 1H-pyrazolo[3,4-e]indolizine, a hitertho unknown tricyclic heteroaromatic system.     

Pyrimidine derivatives. VI. Synthesis of mono-, di-, tri-, and tetrabromo-substituted pyrimidine derivatives

The following bromo-2,4(1H,3H)-pyrimidinediones possessing a bromo substituent at the 5-position and side chains at the 1- and 6-positions were prepared. The three types of mono-bromo derivatives are: 1-(bromoalkyl)-3,6-dimethyl- 3a-d , 5-bromo-3,6-dimethyl-1-(hydroxyalkyl)- 4a-d , and 1-(acetoxyalkyl)-5-bromo-3,6-dimethyl-2,4(1H,3H)-pyrimidinediones 11a-d . The three types of dibromo derivatives are: 5-bromo-1-(bromoalkyl)-3,6-dimethyl- Sa-d , 1-(acetoxyalkyl)-5-bromo-6-bromomethyl- 8a, 8c , and 8d , and 5-bromo-6-bromomethyl 1-(hydroxyalkyl)-2,4(1H,3H)-pyrimidinediones 9a, 9c , and 9d . Likewise one group of tribromo and one group of tetrabromo derivatives are: 5-bromo-1-(bromoalkyl)-6-bromomethyl -7a-d and 5-bromo-1-(bromoalkyl)-6-dibromomethyl-2,4(1H,3H)-pyrimidinediones 6a-d .