Acetamide ferf-butyl

Following the trend towards lower carbonyl IR stretch frequencies, branching alpha to the amide carbonyl (Table 5, entries 53, 54, 62, 63 and 65) affects the shifts for mutagens and hydroxamic esters similarly and causes a marked downfield shift of up to 6 ppm relative to the acetamide substrate (Table 5, entry 60). These effects, as well as the smaller than expected downfield shift with ferf-butyl and neopentyl side chains are, as with the Ai-chlorohydroxamic esters, due to the combined influence of a stabilizing alkyl inductive effect together with destabilizing desolvation of the polar form of the amide carbonyl ". 

Z)-2-(Biphenyl-4-yl)-N-ferf-butyl-2-(cinnamoyloxyimmo)acetamide [4c white solid mp 198-199 °C yield 70% synlanti 100/0)]... 

In particular, the sensitive ferf-butyl ester as the C-terminal protection remained unaffected during both the mild activation procedure and the subsequent conversion of the Tcoc group into the acetamide (Scheme 17). With 32 in hand, the orthogonal stability of the terf-butyl and the Z protecting groups facilitates extension of the peptide chain in the N-terminal direction. 

Environmental chemicals such as p-nonylphenol (NP), 4-ferf.-octylphenol (OP), 4-ferf.-pentylphenol (TPP), bisphenol-A (BPA), tetrabromobisphenol-A (TBBA), butylbenzylphthalate (BBP), di- -butylphthalate (DBP), butylated hydroxyanisole (BHA), p-chloro-ra-cresol, p-chloro-o-cresol, ds-nonachlor, frans-nonachlor, and the herbicide alachlor [2-chloro-iV-(2,6-diethylphenyl)-N-(methoxymethyl) acetamide] have been discovered to be weakly estrogenic [128,129,137,138]. 

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