| 摘要 |
The present invention relates to the preparation of pyrazine derivatives having the formula (1) < IMG > (1) wherein R1 is a hydrogen atom or lower alkyl; R2 is a hydroxy group, an alkoxy group having from 1 to 6 carbon atoms or a group of formula -NR3R4, in which R3 and R4 independently represent a hydrogen atom or an alkyl group having from 1 to 6 carbon atoms; and n is 1 or 0. Compounds of formula (1) whrein n is 0 are prepared starting from diaminomaleonitrile, having formula (2) < IMG > (2) The diaminomaleonitrile is condensed with a compound of formula CHOCOR1 and the resultant compound is reacted with an acid obtaining the pyrazine derivatives of formula (1). Some of the compounds of formula (1) show hypolipaemic and hypoglycaemic activities which are free from side effects of pyridine derivatives; the others are useful intermediates therefor. |
