Ring-fused derivatives of 3,7-diamino- phenothiazinium & phenoselenazinium salts for use as antimicrobial agents

摘要

There are provided compounds of Formula 4: ```wherein:

X

is sulphur or selenium;

Y

comprises a pharmaceutically acceptable anion;

R1 and R9

are each independently H, optionally substituted alkyl, optionally substituted alkoxyl, optionally substituted amine or halogen;

R3a, R3b, R7a and R7b

are each independently H or optionally substituted alkyl with the proviso that at least one of R3a or R3b and/or R7a or R7b, together with the nitrogen atoms to which they are attached, form an optionally substituted, optionally saturated 5, 6 or 7-membered ring with R2 or R4 and/or R6 or R8 respectively; and

R2, R4, R6 and R8

are each independently H, optionally substituted alkyl, optionally substituted alkoxyl, or halogen, so long as at least one of R2, R4, R6 or R8 form a ring as defined above; and the alkyl and alkoxyl groups are preferably saturated;

for use as antimicrobial agents for inhibiting the growth of micro-organisms (such as bacteria, fungi, viruses and protozoa) on or in a medium on exposure to light of wavelength 600 to 800 nm and preferably in the region of 50 to 200 J cm-2. Compositions of such compounds may be formulated with a liquid medium comprising an organic solvent in a mixture with or free from water.