Patent ID: 8053590

Claim:
A compound of the formula IV: where: R1 and R2 are the same or different and are each independently: —(C 6 -C 14 )-aryl where aryl is unsubstituted or mono-, di- or trisubstituted independently by R11, where R11 is F, Cl, I or Br, —(C 1 -C 4 )-alkyl, —CN, —CF 3 , —OR 5 in which R 5 is a hydrogen atom or —(C 1 -C 4 )-alkyl, —N(R 5 )—R 6 in which R 5 and R 6 are each independently a hydrogen atom or —(C 1 -C 4 )-alkyl, —C(O)—R 5 in which R 5 is a hydrogen atom or —(C 1 -C 4 )-alkyl, or —S(O) x —R 5 in which x is the integer zero, 1 or 2, and R 5 is a hydrogen atom or —(C 1 -C 4 )-alkyl, or R1 and/or R2 are a 4- to 15-membered Het ring where the Het ring is unsubstituted or mono-, di- or trisubstituted independently by —(C 1 -C 5 )-alkyl, —(C 1 -C 5 )-alkoxy, halogen, nitro, amino, trifluoromethyl, hydroxyl, hydroxy-(C 1 -C 4 )-alkyl, methylenedioxy, ethylenedioxy, formyl, acetyl, cyano, hydroxycarbonyl, aminocarbonyl or —(C 1 -C 4 )-alkoxycarbonyl; R3 is: —(C 6 -C 14 )-aryl in which aryl is unsubstituted or mono-, di- or trisubstituted independently by —NO 2 , —O—(C 1 -C 4 )-alkyl, F, Cl or bromine; or —O—CH(R7)-aryl in which aryl is unsubstituted or mono-, di- or trisubstituted independently by —NO 2 , —O—CH 3 , F, Cl or bromine, in which R7 is a hydrogen atom or —(C 1 -C 4 )-alkyl; R4 is: a hydrogen atom; —(C 1 -C 4 )-alkyl; or —CH(R8)-aryl in which R8 is a hydrogen atom or —(C 1 -C 4 )-alkyl.