| abstract |
Compounds of the general formula (1), salts thereof and their hydrates. (1) In the formula, each of R, R, R and R independently is a hydrogen atom, etc. R is an optionally substituted phenyl, etc. R is an optionally substituted C aryl, etc. Each of Z and Z independently is a hydrogen atom. They are useful as a therapeutic agent and/or preventive for diseases caused by clot formation, being safer, and have appropriate physicochemical stability. |