| 摘要 |
NEW MATERIAL:The compound of formula I (R1 is methyl or phenyl; R2 is H, methyl or ethyl). EXAMPLE:2,3-Dimethyl-N-(1H-5-tetrazolyl)chromone-8-carboxamide. USE:Antiallergic agent and expectorant. Useful for the remedy of bronchial asthma, allergic gastro-enteropathy, hay fever, uriticaria, allergic rhinitis, etc. PREPARATION:The compound of formula I is obtained by reacting the chromone-8-carboxylic acid halogenide derivative of formula II (X is halogen) with tetrazolylamine of formula III in an inert organic solvent at room temperature - under refluxing. The compound of formula II can be prepared by converting the chromone-8-carboxylic acid derivative to the acid halogenide by conventional method at need. |
