Disclosed herein are compounds of formula (I) wherein L 1 , L 2 , L 3 , L 4 , R 1 , R 4 , R 5 , R 6 , and s are as defined in the specification. Compounds of formula (I) are EP 4 agonists useful in the treatment of glaucoma, osteoporosis, bone fracture, periodontal bone loss, orthopedic implant, alopecia, neuropathic pain, and related disorders. Pharmaceutical compositions and methods of treating conditions or disorders are also described.
