(2R,6R)-2-(thiophen-2-yl)-6-(tritylamino)-1,4-thiazepan-5-one

(R)-tert-butyl 2-(5-oxo-2-(thiophen-2-yl)-6-(tritylamino)-6,7-dihydro-1,4-thiazepin-4(5H)-yl)acetate

tert-butyl 2-((2R,6R)-5-oxo-2-(thiophen-2-yl)-6-(tritylamino)-1,4-thiazepan-4-yl)acetate