Pyrido[2,1-b]quinazolinecarboxylic acids as orally active antiallergy agents

Abstract

A series of 8-substituted pyrido[2,1-]quinazoline-2-carboxylic acids was prepared by the nickel carbonyl mediated carboxylation of the corresponding bromides. The activities of these compounds in the rat PCA test are comparable to those of the corresponding 2-substituted pyrido[2,1-b]quinazoline-8-carboxylic acids.

Phototransformation of three herbicides: chlorbufam, isoproturon, and chlorotoluron. Influence of irradiation on toxicity

“…The first step consists in synthesizing 2-amino-5isopropyl benzoic acid as described by Tilley et al [11]. In a second step the acid chloride is prepared and let to react with dimethylamine.…”

(Acylaryloxy)acetic acid diuretics. 4. Indeno[5,4-b]furan-2-carboxylic acids

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Investigation of the chemistry of the potent new uricosuric diuretic indacrinone led to a class of novel simulated derivatives, indeno [5,[4][5][6]furan-2-carboxylic acids. The structural requirements for optimal diuretic and uricosuric activity of the tricyclic analogues differed from those of their (indanyloxy)acetic acids counterparts.

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“…(5) Habicht, E.; Livis, J. U.S. Patent 3761494, 1973. (6) Kraetz, J.; Criscione, L.; Hedwall, P. Arch. Pharmacol.…”

“…Both the 7-substituted dihydroindenofurans 12 and their tetrahydro analogues 14 were brominated in acetic acid to give the corresponding 7bromo derivatives 15. The 7,8 double bond was introduced by dehydrobromination of 15 with 1,5-diazabicyclo- The indeno [5,[4][5][6]furan-2-carboxyIic acids bearing asymmetric centers at positions 7 (or 8) and 2 consist of two diastereomeric isomer pairs, since the cyclization of intermediates 7 to 8 is nonstereospecific. With one exception (4a,b wherein R = C6H5 and R1 = CH3), no attempt was made to separate the diastereomeric isomer pairs.…”

“…Rat Data. The oral natriuretic activity of the indeno- [5,[4][5][6]furans (determined at four doses) is recorded in Table III. The most potent of the six compounds evaluated was the spirocyclopentyl compound 4d.…”