Prostaglandin pharmaceutical compositions

A method for treating impotence comprising administering to a patient an effective amount of a compound of the formula:

• A—X1—X—X1—NO2 (I)
• wherein A is
• R(CRaRbO)u(COX)t (II)
• wherein t and u are integers and are equal to 0 or 1;
• X═O, NH, NR1c wherein R1c is a linear or branched alkyl having form 1 to 10 carbon atoms;
• Ra and Rb are equal to or different from each other and are H, or a C1-C3 alkyl radical and R is a radical having the following formula:
• wherein m0 is an integer having a value of 0 or 1;
• and when t=1, u=0 and m0=1:
• R1=H;
• an alkyl having from 1 to 6 carbon atoms or a free valance;
• R2=OH, O— such as to form with R1 when R1 is a free valance, and with the carbon atom at position 15 a C═O group;
• R3 and R4 are equal to or different from one another and are equal to R1 or one of them is a bond O—, and the other is a free valance so that with the carbon atom C6 they form a C═O group;
• R5 and R6 are equal to or different from one another, and are equal to R1 when both R5 and R3 are each a free valence, R5 and R3 form a double bond between C5 and C6;
• R7, R8, R9, and R10 are equal to or different from each other, and have the same meaning as R1;
• when R7 or R9, and at the same time R8 or R10 are each a free valence, there is a double bond between C13 and C14;
• R11=R1;
• R12=R11 or OH;
• R13, R14, R15, and R16 are equal to or different from each other, and are equal to R1;
• when R13 or R15, and at the same time R14 or R16, are each a free valence, there is a double bond between C3 and C2;
• R17 and R18 are equal to or different from each other and are equal to R1;
• R19 and R20 are equal to or different from each other and are equal to R1;
• when R6 or R5 is a free valence, and R19 or R20 is a free valence, there is a double bond between C4 and C5;
• R21, R22, R23, and R24 are equal to or different from each other and are equal to R1;
• R25 and R26 are equal to or different from each other and are equal to R1, but both R25 and R26 cannot be a free valence,
• R27 is a linear or branched alkyl having one to six carbon atoms;
• B is equal to the group O═ (a keto group with the carbon atom at position 9 of the prostaglandin molecule) or is OH or —O—;
• when no aliphatic chain C7-C2 is at position 8, there is in its place an alkylaromatic residue:
• which is bound to formula III (B=—O—) in the following way:
• wherein m1 is an integer from 1 to 6,
• Ra and Rb, are equal to or different from each other, and are as defined above, when t=0, u=1, and m0=1 the meanings of the various substituents are as defined above, when t=1, u=0, and m0=0 the meanings of the various substituents are as defined above and C16 is bound, optionally by a bridging group —O—, to an aromatic radical or an alkyl-aryl radical, where the aryl can be substituted, said aryl radical can also contain heteroatoms, such as O or N;
• the alkyl of the alkyl-aryl radical is an aliphatic chain from 1 to 3 carbon atoms;
• X1 of formula A—X1—NO2 is a bivalent connecting bridge, chosen from the following:
• —Y
• where Y is a linear or whenever possible branched C1-C20 alkylene oxygen terminated, or is a C5-C7 cycloalkylene oxygen terminated optionally substituted;
• where n3 is an integer from 0 to 3;
• where nf′ is an integer from 1 to 6;
• and
• where R1f=H or CH3, and nf is an integer from 1 to 6.