Provided are condensed 5-oxazolidinone derivatives and pharmaceutically permissible salts thereof, which have excellent anticoagulant effects, are well absorbed orally, and are useful as therapeutic drugs for thrombosis, etc. Compounds represented by formula (1) and pharmaceutically permissible salts thereof. In the formula, L represents a C1-C4 alkylene group that may be substituted; R11 and R12 each independently represent a hydrogen atom or C1-C6 alkyl group, etc. that may be substituted; X1 represents N or CR1; R1 and R2 each independently represent a hydrogen atom, halogen atom, or C1-C6 alkyl group; Ra represents a C4-C7 cycloalkyl group, etc. that may be substituted; and Rb represents a hydrogen atom, etc.