Carbon-branched carbohydrate chirons: practical access to both enantiomers of 2-C-methyl-ribono-1,4-lactone and 2-C-methyl-arabinonolactone

Readily crystallized 2-C-methyl-d-ribono-1,4-lactone is formed in a one-pot procedure from d-glucose without any protecting groups by treatment with dimethylamine to give an Amadori ketose and then with aqueous calcium hydroxide in yields of approximately 25%; 2-C-methyl-l-ribono-1,4-lactone is similarly produced from l-glucose. 3,4-O-Isopropylidene-2-C-methyl-d-arabinono-1,5-lactone and 2-C-methyl-d-arabinono-1,4-lactone were prepared in a combined 60% yield by the Kiliani reaction of sodium cyanide with a protected 1-deoxy-d-ribulose derived from d-erythronolactone; the enantiomeric arabinonolactones are similarly available from l-erythronolactone.

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2-C-Methyl-d-ribono-1,4-lactoneC6H10O5Ee = 100%[α]D20=+87.6 (c 0.9, H2O)Source of chirality: d-glucose as starting material

2-C-Methyl-l-ribono-1,4-lactoneC6H10O5Ee = 100%[α]D20=-87.6 (c 0.8, H2O)Source of chirality: l-glucose as starting material

2-C-Methyl-d-arabinono-1,4-lactoneC6H10O5Ee = 100%[α]D22=+77.5 (c 1.0, H2O)Source of chirality: d-erythronolactone as starting material

3,4-O-Isopropylidene-2-C-methyl-d-arabinono-1,5-lactoneC9H14O5Ee = 100%[α]D22=-124.7 (c 1.0, CHCl3)Source of chirality: d-erythronolactone as starting material

3,4-O-Methylidene-2-C-methyl-d-arabinono-1,5-lactoneC7H10O5Ee = 100%[α]D21=-126 (c 1.0, CHCl3)Source of chirality: d-erythronolactone as starting material

1-Deoxy-3,4-O-methylidene-d-ribuloseC6H10O4Ee = 100%[α]D21=-61 (c 1.0, CHCl3)Source of chirality: d-erythronolactone as starting material

2,3-O-Methylidene-d-erythrono-1,4-lactoneC5H6O4Ee = 100%[α]D21=-120 (c 1.0, CHCl3)Source of chirality: d-erythronolactone as starting material

2,3-O-Isopentylidene-d-erythrono-1,4-lactoneC9H14O4Ee = 100%[α]D23=-113 (c 1.0, CHCl3)Source of chirality: d-erythronolactone as starting material