Synthesis of cyclocreatine and analogs thereof

A process for the preparation of a compound of formula (I):

• or a pharmaceutically acceptable salt thereof, comprising the step of reacting a compound of formula (II):
• with a compound of formula (III):
• H2N—≡N (III),
• wherein:
• Y is CH2CONR1R2 or CH2CO2R1;
• R1, R2, independently of each other, is hydrogen, lower alkyl, C7-C12 alkyl or cycloalkyl;
• n is 1, 2, 3, 4 or 5;
• and
• wherein a carbon within the parentheses in the compound of formula (I) is optionally substituted with R3 and R4, each of which independently of each other is hydrogen, lower alkyl or cycloalkyl.