Disclosed is a compound (formula (1):(see formula 1)or a pharmaceutically acceptable salt thereof, wherein R1 andR2 are each independently a hydrogen atom or a straight chainalkyl group having a carbon number of 1 - 3, and R2 is ahydrogen atom, an alkyl group having a carbon number of 1 -4, an alkoxyalkyl group, an aryl group, a halogen atom or ahaloalkyl group. The compounds may be used for themanufacture of a medicament for use in the prophylaxis ortreatment of an inflammatory bowel disease.
