Compounds of formula (I) and multimers thereof are inhibitors of
human neutrophil elastase activity, and of utility in the treatment of, e.g.,
COPD:wherein A is
aryl or heteroaryl; D is
oxygen or sulphur; R1, R2 and R3 are independently each
hydrogen,
halogen, nitro, cyano, C1-C6-
alkyl, C2-C6-alkenyl, C2-C6-alkynyl, hydroxy or C1-C6-alkoxy or C2-C6-alkenyloxy, wherein C1-C6-
alkyl and C1-C6-alkoxy can be further substituted with one to three identical or different radicals selected from the group consisting of
halogen, hydroxy and C1-C4-alkoxy;R and R4 each independently represent a radical of formula—[X]m-[Alk1]p-[Q]n-[Alk2]q-[X1]k-Z wherein k, m, n, p and q are independently 0 or 1; Alk1 and Alk2 each independently represent an optionally substituted C1-C6 alkylene, or C2-C6 alkenylene radical which may optionally contain an
ether (O—),
thioether (—S—) or amino (—NRA—) link wherein RA is
hydrogen or C1-C3
alkyl; Q represents (i) O—, —S—, —S(═O)—, —S(═O)2—, —S+(RA)—, —N(RA)—, —N+(RA)(RB)—, —C(═O)—, —C(═O)O—, —OC(═O)—, —C(═O)NRA—, —NRAC(═O)—, —S(O2)NRA—, —NRAS(O2)—, —NRAC(═O)NRB—, —NRAC(═NRA)NRB—, —C(═NRD)NRE, —NREC(═NRD), wherein RA, RB, RD and RE are independently
hydrogen, C1-C6 alkyl, or C3-C6 cycloalkyl, or RA and RB, or RD and RE taken together with the
nitrogen to which they are attached form a monocyclic heterocyclic ring of 5 to 7 ring atoms which my contain a further
heteroatom selected from N, O and S, or (ii) an optionally substituted
divalent mono- or bicyclic carbocyclic or heterocyclic radical having 3-6 ring members; X represents —(C═O)—, —S(O2)—, —C(═O)O—, —(C═O)NRA—, or —S(O2)NRA—, wherein RA is hydrogen, C1-C6 alkyl, or C3-C6 cycloalkyl; X1 represents —O—, —S—, or —NH; and Z is hydrogen or an optionally substituted mono- or bicyclic carbocyclic or heterocyclic radical having 3-6 ring members.