Bis-aromatic a,β-unsaturated ketones

bis-Aromatic a,β-unsaturated ketones of the general formula IX

• wherein R2 and R4 designates RH or H, where RH designates C1-6 straight or branched aliphatic hydrocarbyl which may be saturated or may contain one or more unsaturated bonds selected from double bonds and triple bonds, R′6 designates A(W*)p and R′8 designates H, wherein W* designates H, RH or a masking group Z that is selected from the following groups (A)-(E):
• —CO—R′ (A)
• —CON(CH3)2 (B)
• —CR*R**—O—R″ (C)
• —CR*R**—O—CO—R′″ (D)
• wherein in the above (A)-(E) R* and R** each independently designate hydrogen or C1-3 alkyl;
• R′, R″ and R′″ each designate C1-6 alkyl, or is an aromatic group Ar1 or Ar2 that are the same or different and may be phenyl, or a 5- or 6-membered unsaturated heterocyclic ring containing 1-3 N, O or S atoms, and which Ar1 or Ar2 groups may be optionally substituted with one or more substituents selected from the group consisting of halogen, nitro, nitroso, C1-12 straight or branched aliphatic hydrocarbyl which may be saturated or may contain one or more double or triple bonds, which hydrocarbyl may be substituted with one or more of hydroxy, halogen, amino and amino optionally alkylated with one or two C1-6 alkyl groups, A designates S, N or O, whereby, when A designates S or O, then p designates 1, and when A designates N, then p designates 2, or R′8 designates A(W*)p and R′6 designates H, wherein W* designates H, RH or a masking group Z as defined above, A designates N, S or O, whereby, when A designates S or O, then p designates 1, and when A designates N, then p designates 2, or both R′6 and R′8 designate H, with the proviso that when R2 and R4 both are H, then at least one W* designates a masking group Z as defined above, whereby when the masking group is a group —CO—R′, then R′ is C2-6 alkyl or is an aromatic group Ar1 or Ar2 as defined above, and RH is C1-6 straight or branched chain aliphatic hydrocarbyl which may be saturated or may contain one or more double or triple bonds,
• with the exception of licochalcone A, licochalcone C, 3-[4-hydroxy-5-(1,1-dimethylprop-2-enyl)-2-methoxyphenyl]-1-[4-(methoxymethoxy)phenyl]-2-propen-1-one, 3-[4-acetyloxy-5-(1,1-dimethylprop-2-enyl)-2-methoxyphenyl]-1-[4-(methoxymethoxy)phenyl]-2-propen-1-one, 3-[5-(1,1-dimethylprop-2-enyl)-2,4-dimethoxyphenyl]-1-[4-(methoxy)phenyl]-2-propen-1-one, 3-(4-acetyloxy-5-(1,1-dimethylprop-2-enyl)-2-methoxyphenyl]-1-(4-acetyloxyphenyl)-2-prop-1-one, 3-(2-hydroxy-4-methoxy-3-(3-methylbut-2-enyl)phenyl]-1-[4-[(3,7,11-trimethyl-2,6-dodecatri-10-enyl)oxy]phenyl]-2-prop-1-one, 2,4-dihydroxy-3-methylchalcone, and 1-[4-(methoxy)phenyl]-3-[2-methoxy-4-[3-(methyl-2-butenyl)oxy]-2-propenone-1.