Studies on antianaphylactic agents. 5. Synthesis of 3-(1H-tetrazol-5-yl)chromones, a new series of antiallergic substances

Abstract

A number of 3-(1H-tetrazol-5-yl)chromones were synthesized and found to have antiallergic activity in the rat passive cutaneous anaphylaxis (PCA) test. These compounds are active when administered orally in rats and of possible value for the treatment of asthma.

Antiallergic action of 6-ethyl-3-(1h-tetrazol-5-yl) chromone (aa-344) on immediate hypersensitivity reaction in rats

“…In recent years, baicalein having the same chromone structure as DSCG, which is the aglycone of baicalin present in Scutellaria baicalensis Georg, and its water-soluble derivative, disodium baicalein-6-phosphate have been found to inhibit allergic reactions in experimental models (6). In our continued research to develop a more potent orally effective antiallergic agent, a number of chromone derivatives were synthesized and tested biologically (7,8). One of these derivatives, 6-ethyl-3-(1H-tetrazol-5-yl)chromone (AA-344) was found to be highly effective, when given orally, in inhibiting passive cutaneous anaphylaxis (PCA) after a 72-hr latent period in rats.…”

Synthesis and reactions of 8-allylchromone-3-carboxaldehyde

“…It has been reported that chromone derivatives bearing an acidic groups at position 3 displayed antiallergic activities. 19,20 Thus, in the present work some analogous compounds containing the allyl moiety at position 8 were prepared. Reaction of the carbonitrile 9 with sodium azide in the presence of aluminum chloride in tetrahydrofuran afforded 8-allyl-3-(1H-tetrazol-5-yl)chromone 10.…”

3-Formylchromones as diverse building blocks in heterocycles synthesis

“…Synthesis of trans-β-(4-oxo-4H-chromen-3-yl)acrylonitrile 51 was made by simple condensation of 3-formylchromones 1a,b with cyanoacetic acid in dry pyridine under reflux (Scheme 23) [46,47].…”