Imines, glucosamine-derived

Glucosamine-derived imines 58 were used for the synthesis of carbapenem and carbacephem antibiotics. [2 + 2] Cycloaddition with methoxyacetyl chloride provided diastereomeric S-lactams with low asymmetric induction [56]. Radical cyclization and oxidation reactions of diastereoisomer 59 led to car-bapenems 60 and 61 (Scheme 16) [57]. The same research group continued the transformation of S-lactams derived from o-glucosamine. In particular, a tandem ehmination-conjugate addition performed on 62 provided the second ring of the carbacephem, for example 63 (Scheme 17) [58]. 

Ketene-imine cycloaddition involving an imine derived from cinnam-aldehyde and a D-glucosamine derivative led stereoselectively to the p-lactam (110) the chiral auxiliary could be disconnected from the p-lactam by base treatment. Cycloaddition of methyl acrylate and an N-glycosyl dihydropyridine gave adduct (111) and its diastereomer in the azabicyclic ring system. Removal of the chiral auxiliary from each diastereomer then gave the enantiomeric isoquinuclidines. ... 

Treatment of iV-acetyl-D-glucosamine with dilute alkali is reported to give 3-ace-tamidofuran 192 (R1 = R2 = R3 — 11, R4 = Me) (56CB1473). An imine derivative of 3-aminofuran has been obtained by reaction of 3-furyllithium with the oxime 0-tosylate of tetraphenylcyclopentadienone (84JA5753). 

Scheme 30.11 Imine-hydrocyanation using urea-catalyst 44 derived from D-glucosamine.

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