[1,2,4]Triazolo[4,3-A]pyrazin-6(5H)-one derivatives
The present invention provides a compound of Formula (I), wherein X is H or C1-C3 alkyl optionally substituted with hydroxyl; Y is H, hydroxy, or methyl; R is ethyl, n-propyl, cyclopropyl, or Formula (II); and A is methyl, cyclopropyl or trifluoromethyl; or a pharmaceutically acceptable salt thereof; with the proviso that when X and Y are both H and R is n-propyl, then A is other than methyl; for use as a human PDE1 inhibitor.
1. A compound of the formula:
wherein X is H or C1-C3 alkyl optionally substituted with hydroxyl;
Y is H, hydroxy, or methyl;
R is ethyl, n-propyl, cyclopropyl, or
and
A is methyl, cyclopropyl or trifluoromethyl;
or a pharmaceutically acceptable salt thereof;
with the proviso that when X and Y are both H and R is n-propyl, then A is other than methyl.
2. The compound or salt according to claim 1 wherein X is methyl.
3. The compound or salt according to claim 1 wherein Y is H.
4. The compound or salt according to claim 1 wherein R is n-propyl.
5. The compound or salt according to claim 1 wherein A is cyclopropyl.
6. The compound according to claim 1 wherein the compound is in the free base form.
7. The compound or salt according to claim 1 wherein the compound is of the formula:
8. The compound according to claim 1 wherein the compound is of the formula:
9. The compound or salt according to claim 1 wherein the compound is of the formula:
10. The compound according to claim 1 wherein the compound is of the formula:
11. A pharmaceutical composition, comprising a compound or a pharmaceutically-acceptable salt thereof according to claim 1 , with one or more pharmaceutically acceptable carriers, diluents, or excipients.
12. A process for preparing a pharmaceutical composition, comprising admixing a compound according to claim 1 , or a pharmaceutically-acceptable salt thereof, with one or more pharmaceutically acceptable carriers, diluents, or excipients.