for the following products
(2S,3R)-3-(Tert-butoxy)-2-{[(tert-butoxy)carbonyl]amino}butanoic acid | Boc-L-Thr(tBu)-OH | Boc-Thr(But)-OH | Boc-Thr(tBu)-OH | N-alpha-tert-Butyloxycarbonyl-O-tert-Butyl-L-threonine | N-S-tert-Boc-o-tert-Butyl-L-threonine and Boc-O-tert-Butyl-L-threonine
