| abstract |
A compound of the ** formula **, in which R1 represents a hydrogen atom or a radical SR4 or NR4R5; R2 represents SR6 or NR6R7; R3 represents OH, O (CO) R14, OSiR15R16R17, O (CO) OR18 or O (CO) NHR18; R4 and R6 independently represent an alkyl radical, a cycloalkyl, cycloalkylalkyl, hydroxyalkyl radical or also one of the aryl or aralkyl radicals optionally substituted on their aryl group with one or more radicals chosen from the alkyl, hydroxy or alkoxy radicals, R5 and R7 independently represents a hydrogen atom, an alkyl radical, a cycloalkyl, cycloalkylalkyl, hydroxyalkyl radical or also one of the optionally substituted aryl or aralkyl radicals on its aryl group with one or more radicals chosen from the alkyl, hydroxy or alkoxy radicals , or a salt of a compound of the general formula. |