A compound of formula I wherein: R7 is selected from: ORA, where RA is selected from C1-4 saturated alkyl, optionally substituted by phenyl, which may bear a chloro substituent, pyridyl and furanyl; chloro; NH2; -CH2-O-C(=O)Me; R8 is OProt°, where Prot° is a silicon-based oxygen protecting group orthogonal to Rc; R9 is selected from H, methyl and methoxy; Rs is selected from CF3, (CF2)3CF3, CH3 and (formula 2) and Rc is selected from: (i) -C(=O)-ORC1, where RC1 is a saturated C1-4 alkyl group; (ii) -CH2-O-C(=0)RC2, where RC2 is methyl or phenyl; (iii) -CH2-O-Si-(RSi1)(RSi2)(RSi3), where RSi1, RSi2, RSi3 are independently selected from C1-6 a saturated alkyl group and a phenyl group; and (iv) -C(-YRC3)(-YRC4) where each Y is independently O or S, and where RC3 and RC4 are independently a saturated C1-4 alkyl group, or together form a C2-3 alkylene.
式I的化合物,其中:R7选自:ORA,其中RA选自C1-4饱和烷基,可选择地被苯基取代,该苯基可能带有
氯取代基,
吡啶基和
呋喃基;
氯;NH2;-
CH2-O-C(=O)Me;R8为OProt°,其中Prot°是与Rc正交的基于
硅的氧保护基团;R9选自H,甲基和甲氧基;Rs选自
CF3,(
CF2)3 ,
CH3和(式2);Rc选自:(i)-C(=O)-ORC1,其中RC1是饱和的C1-4烷基基团;(ii)- -O-C(=0)RC2,其中RC2是甲基或苯基;(iii)- -O-Si-(RSi1)(RSi2)(RSi3),其中RSi1,RSi2,RSi3分别选自C1-6饱和烷基和苯基;以及(iv)-C(-YRC3)(-YRC4),其中每个Y独立地为O或S,且RC3和RC4独立地为饱和的C1-4烷基基团,或者一起形成C2-3亚烷基。