CGRP Antagonist Peptides

A compound of formula (I) or a pharmaceutically acceptable salt thereof:

• wherein
• m is 0, 1, 2, 3, 4, or 5;
• p is 0, 1, 2, or 3;
• A is single or double carbon-carbon bond;
• Ar1 is aryl or 5- or 6-membered heteroaryl, each of which is optionally substituted with one or more substituents, each substituent independently being halogen, nitro, C1-C4 alkyl, C1-C4 hydroxyalkyl, ORa, or N(RaRa′), in which each Ra, independently, is H or C1-C4 alkyl and each Ra′, independently, is H or C1-C4 alkyl;
• Ar2 is aryl or 5- or 6-membered heteroaryl, each of which is optionally substituted with one or more substituents, each substituent independently being halogen, cyano, nitro, C1-C4 alkyl, C1-C4 aminoalkyl, C1-C4 hydroxyalkyl, ORb, N(RbRb′), C(O)—N(RbRb′), or NH—C(O)—N(RbRb′), in which each Rb, independently, is H or C1-C4 alkyl and each Rb′, independently, is H or C1-C4 alkyl;
• Ar3 is aryl or 5- or 6-membered heteroaryl, each of which is optionally substituted with one or more substituents, each substituent independently being halogen, C1-C4 alkyl, C1-C4 hydroxyalkyl, ORc, or N(RcRc′), in which each Rc, independently, is H or C1-C4 alkyl and each Rc′, independently, is H or C1-C4 alkyl;
• each R1, independently, is C1-C4 alkyl, C1-C4 aminoalkyl, C1-C4 hydroxyalkyl, ORd, or C(O)—N(RdRd′), in which each Rd, independently, is H or C1-C4 alkyl and each Rd′, independently, is H or C1-C4 alkyl;
• R2 is —(CH2)n—R, in which n is 0, 1, 2, or 3 and R is substituted or unsubstituted guanidino, aminoacyl, C1-C4 alkylaminoacyl, ORe, N(ReRe′), NH—C(O)—CH(NH2)—(CH2)4—N(ReRe′), NH—C(O)—CH2—(OCH2CH2)2—N(ReRe′), or 5-membered heterocycloalkyl optionally substituted with C1-C4 alkyl or N(ReRe′), in which each Re, independently, is H or C1-C4 alkyl and each Re′, independently, is H or C1-C4 alkyl;
• and
• each R3, independently, is halogen, C1-C4 alkyl, or ORf, in which each Rf, independently, is H or C1-C4 alkyl;
• with the provisos that, when n is 0, R is not amino or guanidino and that, when the amino acid residue bonded to Ar1C(O) is L-Val, Ar1 is not unsubstituted phenyl.