Hydantoin-containing glucokinase activators

A compound of the formula:

• wherein
• R1 is a five- or six-membered aromatic heterocyclic ring having one to three heteroatoms selected from nitrogen, oxygen, and sulfur, which ring is unsubstituted or substituted with halo, amino, hydroxylamino, nitro, cyano, sulfonamido, lower alkyl, perfluoro lower alkyl, lower alkyl thio, perfluoro-lower alkyl thio, lower alkyl sulfonyl, perfluoro-lower alkyl sulfonyl, lower alkyl sulfinyl, or —(R5)n—C(O)—OR6;
• R2 is a cycloalkyl ring containing from 5 to 7 carbon atoms;
• R3 is hydrogen, lower alkyl, a cycloalkyl ring containing from 5 to 7 carbon atoms, unsubstituted aryl, or aryl substituted with halo or hydroxy;
• R4 is hydrogen or lower alkyl;
• R5 is —C(O)— or lower alkyl;
• R6 is lower alkyl;
• n is 0 or 1;
• * and ** each designate an asymmetric centers
• and pharmaceutically acceptable salts thereof.