“…To the best of our knowledge, the trisubstituted C=C bond of angelic acid esters 3 (Figure 1), and derivatives thereof, is the only SAD site at which, according to the literature, configurational control was incongruent, at least in one instance contradictory, and in part in conflict with the Sharpless mnemonic (Scheme , see below) 11–19. This investigation unravels the steric course of the SAD of esters and amides of methacrylic acid,20 tiglic acid,21 and angelic acid22 unambiguously (see below); enantiomerically pure (in most cases) or enriched (occasionally) 1,2‐diols obtained from such substrates were used in the construction of complex natural products,20k,21b,21c represented drug candidates,20h,20j served as building blocks for peptides [20a,20c,20e–20g,21a,22b] or became the progenitor of other diverse products.…”