Stable pharmaceutical compositions

A compound having the formula:

• 64
• or a compound having the formula:
• 65
• where R1 and R2 are independently H, branched or straight chain alkyl having from 2 to about 7 carbon atoms, unsubstituted aryl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aralkyl, substituted or unsubstituted alkylcycloalkyl, lower alkenyl;
• where R3 is a branched or straight chain alkyl having from 2 to about 7 carbon atoms, substituted or unsubstituted aryl, substituted or unsubstituted aralkyl, substituted or unsubstituted cycloalkyl, aralkyl, substituted or unsubstituted alkylcycloalkyl or a group having the formula (CH2)nCOOH where n is from 3 to about 7;
• with the proviso that when R1 is H or methyl, then R2 is a branched or straight chain alkyl having from 2 to about 7 carbon atoms, substituted or unsubstituted aryl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aralkyl, substituted or unsubstituted alkylcycloalkyl, lower alkenyl.

A particulate-free hydralazine composition comprising compound having the formula:

• 67
• or a compound having the formula:
• 68
• where R1 and R2 are independently H, substituted or unsubstituted branched or straight chain alkyl having from 1 to about 7 carbon atoms, substituted or unsubstituted aryl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aralkyl, substituted or unsubstituted alkylcycloalkyl, lower alkenyl or R1 and R2 together form part of a substituted or unsubstituted cycloalkyl having from about 4 of about 7 carbon atoms;
• where R3 is a branched or straight chain alkyl having from 1 to about 7 carbon atoms, substituted or unsubstituted aryl, substituted or unsubstituted aralkyl, substituted or unsubstituted cycloalkyl, aralkyl, substituted or unsubstituted alkylcycloalkyl or a group having the formula (CH2)nCOOH where n is from 1 to about 7 in a pharmaceutically acceptable salt or diluent.

A metal ion-free hydralazine composition comprising a compound having the formula:

• 69
• or a compound having the formula:
• 70
• where R1 and R2 are independently H, branched or straight chain alkyl having from 1 to about 7 carbon atoms, substituted or unsubstituted aryl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aralkyl, substituted or unsubstituted alkylcycloalkyl, lower alkenyl or R1 and R2 together form part of a substituted or unsubstituted cycloalkyl having from about 4 of about 7 carbon atoms;
• where R3 is a branched or straight chain alkyl having from 1 to about 7 carbon atoms, substituted or unsubstituted aryl, substituted or unsubstituted aralkyl, substituted or unsubstituted cycloalkyl, aralkyl, substituted or unsubstituted alkylcycloalkyl or a group having the formula (CH2)nCOOH where n is from 1 to about 7;
• in a pharmaceutically acceptable salt or diluent;
• and wherein said compound in said hydralazine composition does not complex with metal ions.