Asymmetric Synthesis of the Putative Structure of (−)-Oryzoxymycin

Abstract

[reaction: see text] A short asymmetric synthesis of (2'S,5R,6R)-2'-[6-amino-5-hydroxy-1,3-cyclohexadiene-1-carbonyloxy]propionic acid, the enantiomer of the reported structure of (+)-oryzoxymycin is described. The reported spectral data does not match that obtained for synthetic "oryzoxymycin".

Diversity‐Oriented Production of Metabolites Derived from Chorismate and Their Use in Organic Synthesis

“…The complementary of 5 and 9 was emphasized by the synthesis of both enantiomers of the natural product valienone (19) starting from these compounds (Scheme 3). [16] 1,2-Amino alcohols are prevalent in natural products and pharmaceuticals, for example in adrenaline and beta blockers.…”

“…The relative configuration of 3 was verified by single-crystal X-ray structure analysis of the corresponding bisacetyl-protected methylester 20 (see the Supporting Information). Steel et al [19] recently reported that 3, synthesized in racemic form, can be oxidized stereoselectively analogous to the oxidation of the diols 5 and 9. Furthermore, 3 and derivatives thereof have been used in cycloaddition reactions.…”

β- and σ-Amino acids (2,3- and 3,4-trans-CHA) as catalysts in Knoevenagel condensation and asymmetric aldol reactions

“…While the two amino acids 2,3-trans-CHA (2) and 3,4-trans-CHA (4) proved to be just as good as the L-proline catalyst with respect to enantioselectivity, they intrinsically possess several advantages. As we and others have shown for 2 and 4, and for the respective diols 2,3-trans-CHD (3) and 3,4-trans-CHD (5), 39,41,48,49 the carboxylate moiety and the vicinal diol or amino alcohol moieties can be protected selectively. The 1,3-diene system of these compounds can be modified highly specifically through oxidative or reductive processes (e.g., epoxidation, dihydroxylation, selective hydrogenation), as well as via pericyclic reactions such as Diels-Alder and hetero-Diels-Alder additions (Scheme 5).…”

Synthesis of enantiopure trans‐N‐Boc‐3‐aminobicyclo[2.2.2]octane‐2‐carboxylic acids and their bicyclic 1,3‐amino alcohol derivatives via the [4+2] cycloaddition of 1,3‐cyclohexadiene to a chiral β‐nitroacrylate

“…1 They act as electron deficient alkenes and react with different dienes to yield cyclic constrained b-amino acids after reduction of the nitro group. [2][3][4][5] Concerning asymmetric Diels-Alder syntheses, it is surprising that only a few methods involving the use of a chiral b-nitroacrylate have been reported so far. 6,7 Indeed, chiral cyclic b-amino acids are an important class of compounds as they are constituents of natural products such as alkaloids, peptides, and b-lactam antibiotics.…”