Abstract: The present invention relates to compounds of the general structure: wherein Y is O, X is O, bond ? is absent and bond ? is present, or Y is H, X is CH, bond ? is present, and bond ? is absent; atom Z is a carbon and bonds ?, ? and ? are present, or is a nitrogen and bonds ?, ? and ? are absent; R1 is —H, —OH, —O—R7, —N(H)—R8, —N(H)—(CH2)n—NH2, —N(R9)(R10), or a piperazine cation; R2 is either covalently bound to R9, or is —H, or is covalently bound to R3 so as to form a substituted or unsubstituted pyrrole or R2 is covalently bound to R9 or R8 or R7; or R1 and R2 are covalently joined to form an aromatic ring; R3 is either covalently bound to R2 so as to form a pyrrole, or is, inter alia, —H, —OH, alkyl, or when Z is nitrogen R3 is ?O; R4 is, inter alia, —H, —OH, or —R11NH2; R5 is, inter alia, —H, —OH, or —R12NH2, and R6 is either is covalently bound to R10 or is —H, or R6 is covalently bound to R10 or R8 or R7.

Abstract: The present invention relates to compounds of the general structure: wherein Y is O, X is O, bond ? is absent and bond ? is present, or Y is H, X is CH, bond ? is present, and bond ? is absent; atom Z is a carbon and bonds ?, ? and ? are present, or is a nitrogen and bonds ?, ? and ? are absent; R1 is —H, —OH, —O—R7, —N(H)—R8, —N(H)—(CH2)n—NH2, —N(R9)(R10), or a piperazine cation; R2 is either covalently bound to R9, or is —H, or is covalently bound to R3 so as to form a substituted or unsubstituted pyrrole or R2 is covalently bound to R9 or R8 or R7; or R1 and R2 are covalently joined to form an aromatic ring; R3 is either covalently bound to R2 so as to form a pyrrole, or is, inter alia, —H, —OH, alkyl, or when Z is nitrogen R3 is ?O; R4 is, inter alia, —H, —OH, or —R11NH2; R5 is, inter alia, —H, —OH, or —R12NH2, and R6 is either is covalently bound to R10 or is —H, or R6 is covalently bound to R10 or R8 or R7.