Synthesis, antibacterial and antiviral properties of curcumin bioconjugates bearing dipeptide, fatty acids and folic acid

Curcumin bioconjugates, viz. di-O-tryptophanylphenylalanine curcumin (2), di-O-decanoyl curcumin (3), di-O-pamitoyl curcumin (4), di-O-bis-(γ,γ)folyl curcumin (6), C(4)-ethyl-O-γ-folyl curcumin (8) and 4-O-ethyl-O-γ-folyl curcumin (10) have been synthesized and tested for their antibacterial and antiviral activities. The conjugates 2, 3, 4, 6 and 8 have shown very promising antibacterial activity with MIC ranging between 0.09 and 0.67 μM against Gram-positive cocci and Gram-negative bacilli. Further, the conjugates 2, 3, 6, 8 and 10 have been screened for their antiviral activities against HSV, VSV, FIPV, PIV-3, RSV and FHV and the molecules 2 and 3 have shown good results with EC(50) 0.011 μM and 0.029 μM against VSV and FIPV/FHV, respectively. However, the molecules did not show expected results against HIV-1 III(B) and ROD strains in MTT assay.