Selective neurokinin antagonists
Compound represented by the structural formula or a pharmaceutically acceptable salt thereof, wherein Ar1 and Ar2 are optionally substituted heteroaryl or optionally substituted phenyl; X1 is -O-, -S-, -SO-, -SO2-, -NR12-, -NCOR12- or -NR12SO2R15; is selected from the group consisting of X2 is -O-, -S- or -NR5-; Y is =O, =S or =NR11; Y1 is H, C1-C6 alkyl, -NR17R13, -SCH3, R19-aryl(CH2)n6-, R19-heteroaryl-(CH2)n6-, -(CH2)n6-heterocycloalkyl, -(C1-C3)alkyl-NH-C(O)O(C1-C6)alkyl or -NHC(O)R15; R5 is H or -(CH2)n1-G, wherein n2 is 0-5, G is H, -CF3, -CHF2, -CH2F, -OH, -O-(C1-C6 alkyl), -SO2R13, -O-(C3-C8 cycloalkyl), -NR13R14, -SO2NR13R14, -NR13SO2R15-NR13COR12, -NR12(CONR13R14), -CONR13R14, -COOR12, C3-C8 cycloalkyl, R19-aryl, R19</superscript></hi