Oxanilic acids, a new series of orally active antiallergic agents

Abstract

A large number of oxanilic acid esters and N-heteroaryl oxamic acid esters were prepared and found to have antiallergic activity using the rat passive cutaneous anaphylaxis (PCA) test. Many of the oxanilic acid esters are active orally, with the most active species having an aryl 2'-carbamoyl group and a 3'-methoxy group. Hydrolysis of the ester from the oxanilic ester moiety causes a loss of oral activity.

Antiallergic properties of an orally effective agent,((3-(1H-tetrazol-5-yl)-phenyl)amino) oxoacetic acid n-butyl ester.

“…The hydrolysis of an ester from the oxanilic ester moiety resulted in a loss of oral activity (14). We also examined the oral activity of several alkyl esters of oxanilic acid, and the butyl ester was found to have the maximum activity (unpublished data).…”

A new protocol for the synthesis of primary, secondary and tertiary anthranilamides utilizing N-(2-aminoarylacyl)benzotriazoles

“…3c, 4 In addition, some amide derivatives of anthranilic acid show biological activities 5 or they are the starting materials for o-aminonitriles which are versatile synthons to get some useful heterocycles. 6 Literature methods for synthesizing anthranilamides are: (i) the reaction of anthranilic acid with amine in the presence of various reagents (SOCl2, 7a ) (ii) the reaction of anthranilesters with amines, 8 (iii) the catalytically reduction of 2-nitrobenznitriles, 9 (iv) the reaction of 2-nitrobenzoic acid activated by SOCl2 with an amine, and then catalytically reduction of nitro group, 7f,10 and (v) the reaction of isatoic anhydride with various amines 7c,f,11,12 (Scheme 1). These methods developed to get anthranilamides have some disadvantages like being lack of wide generality in use, having harsh reaction conditions or complex reaction steps.…”

Dibutyltin oxide catalyzed aminolysis of oxalate to carbamate, oxamate and derivatives of imidazolidine trione

“…Oxamate functionality has been found to play a vital role in many drugs, e.g. oxamate derivatives are used as orally active antiallergic agents 6. Oxamate functionality has been also found to play a vital role as a potent antimalarial drug.…”