1. An EP4 agonist containing a compound represented by the formula (1): wherein each of the substituents R and R independently represents a hydrogen atom or a straight chain alkyl group comprising from 1 to 3 carbon atoms, and R denotes a hydrogen atom, an alkyl group comprising from 1 up to 4 carbon atoms, an alkoxyalkyl group, an aryl group, a halogen atom or a haloalkyl group, or a pharmaceutically acceptable salt thereof. 2. An EP4 agonist according to claim 1, wherein R represents a methyl group. An EP4 agonist according to claim 1 or 2, where R is a methyl group. An EP4 agonist according to claim 1, where R is a hydrogen atom. An EP4 agonist according to claim 1, where R is a methyl group and R is a hydrogen atom. An EP4 agonist according to claim 1, where R is an m-methyl group. The agonist of EP4 according to claim 1, where R is a methyl group, R is a hydrogen atom and R is a methyl group. The agonist of EP4 according to claim 1, where R is a hydrogen atom, R is a methyl group and R is a methyl group. The EP4 agonist according to claim 1, which is 4 - [(Z) - (1S, 5R, 6R, 7R) -6 - [(1E, 3R, 4RS) -3-hydroxy-4- (m-tolyl) - 1-pentenyl] -7-hydroxy-2-oxa-4,4-difluorobicyclo [3.3.0] octan-3-ylidene] -1- (tetrazol-5-yl) butane or its pharmaceutically acceptable salt. 10. The EP4 agonist according to claim 1, which is 4 - [(Z) - (1S, 5R, 6R, 7R) -6 - [(1E, 3R, 4R) -3-hydroxy-4- (m-tolyl) - 1-pentenyl] -7-hydroxy-2-oxa-4,4-difluorobicyclo [3.3.0] octan-3-ylidene] -1- (tetrazol-5-yl) butane or its pharmaceutically acceptable salt. 11. The EP4 agonist according to claim 1, which is 4 - [(Z) - (1S, 5R, 6R, 7R) -6 - [(1E, 3R, 4S) -3-hydroxy-4- (m-tolyl) - 1-pentenyl] -7-hydroxy-2-oxa-4,4-difluorobicyclo [3.3.0] octan-3-ylidene] -1- (tetrazol-5-yl) butane or its pharmaceutically acceptable salt. 12. A medicament comprising an EP4 agonist according to any one of claims 1 to 11 as an active ingredient. Lek�1. Агонист EP4, содержащий соединение, представленное формулой (1):гд
