Fine-Tuning the Selectivity of Aldosterone Synthase Inhibitors: Structure−Activity and Structure−Selectivity Insights from Studies of Heteroaryl Substituted 1,2,5,6-Tetrahydropyrrolo[3,2,1-ij]quinolin-4-one Derivatives
摘要:
Pyridine substituted 3,4-dihydro-1H-quinolin-2-ones (e.g., 1-3) constitute a class of highly potent and selective inhibitors of aldosterone synthase (CYP11B2), a promising target for the treatment of hyperaldosteronism, congestive heart failure, and myocardial fibrosis. Among these, ethyl-substituted 3 possesses high selectivity against CYP1A2. Rigidification of 3 by incorporation of the ethyl group into a 5- or 6-membered ring affords compounds with a pyrroloquinolinone or pyridoquinolinone molecular scaffold (e.g., 4 and 5). It was found that these molecules are even more potent and selective CYP11B2 inhibitors than their corresponding open-chain analogues. Moreover, pyrroloquinolinone 4 exhibits no inhibition of the six most important hepatic CYP enzymes as well as a bioavailability in the range of the marketed drug fadrozole. The SAR studies disclose that subtle changes in the heterocyclic moiety are responsible for either a strong or a weak inhibition of the highly homologous 11 beta-hydroxylase (CYP11B1). These results are not only important for fine-tuning the selectivity of CYP11B2 inhibitors but also for the development of selective CYP11B1 inhibitors that are of interest for the treatment of Cushing's syndrome and metabolic syndrome.
An object of the present invention is to provide to a compound and a pharmaceutical composition, which have excellent Syk-inhibitory activity. The present invention provides a nicotinamide derivative represented by the following formula (I) (wherein R
1
represents a halogen atom; R
2
represents a C
1-12
alkyl group, a C
2-12
alkenyl group, a C
2-12
alkynyl group, a C
3-8
cycloalkyl group, an aryl group, an ar-C
1-6
alkyl group or a heterocyclic group, each optionally having at least one substituent; R
3
represents an aryl group or a heterocyclic group each optionally having at least one substituent; and R
4
and R
5
each independently represent a hydrogen atom; and R
2
and R
4
may form a cyclic amino group optionally having at least one substituent together with the nitrogen atom to which they bind) or a salt thereof, and a pharmaceutical composition for use in the treatment of a Syk-related disease which comprises the nicotinamide derivative or a salt thereof.