A FACILE AND PRACTICAL SYNTHESIS OF 9-METHYL-3-(1H-TETRAZOL-5-YL)-4H-PYRIDO[1,2-A]PYRIMIDIN-4-ONE

被引：0

作者：

SANO, A

ISHIHARA, M

YOSHIHARA, J

SUMINO, M

NAWA, H

机构：

来源：

CHEMICAL & PHARMACEUTICAL BULLETIN | 1995年 / 43卷 / 04期

关键词：

ANTIASTHMA AGENT; 1H-TETRAZOLE; 4H-PYRIDO[1,2-A]PYRIMIDINE; SODIUM AZIDE; ALTERNATIVE SYNTHESIS; ONE-POT SYNTHESIS;

D O I：

暂无

中图分类号：

R914 [药物化学];

学科分类号：

100701 ;

摘要：

A facile and practical synthesis of 9-methyl-3-(1H-tetrazol-5-yl)-4H-pyrido[1,2-a]pyrimidin-4-one (4), the potassium salt of which is used clinically as an anti-asthma agent, is described. Treatment of a key intermediate (6b), prepared from 2-amino-3-methylpyridine (1) and 2-ethoxymethylene-1,3-propanedinitrile, with sodium azide in N,N-dimethylformamide gave predominantly the cyanotetrazole (7a), while in acetic acid it gave exclusively the iminotetrazole (7b), which was easily converted into 4 by acid hydrolysis. A one-pot process starting from 6b to give 4, avoiding the use of explosive aluminum azide, was established.

引用

页码：683 / 685

页数：3

共 9 条

[1]

Herbst R.M., 1950, J ORG CHEM, V15, P1082, DOI [DOI 10.1021/JO01151A027, 10.1021/jo01151a027]

[2] APPARENT ACIDIC DISSOCIATION OF SOME 5-ARYLTETRAZOLES [J].