Decilorubicin (1) is an antitumor antibiotic produced by Streptomyces uirginiae' whose structure was determined by a combination of chemical conversions, degradations and spectral interpretation'. Herein we describe the synthesis of 3-amino-5-Cphenyl-D-altrofuranose and 3-amino-5-C-[3-carboxy-4-(carboxymethyl)-2-oxo-3-cyclohexen-1 -yl]-D-altrofuranose (or L-galactofuranose), possible intermediates for the synthesis of the chromophore of decilorubicin' having the 4-amino-2,6-epoxybenz[g]oxocane ring (DEF) system*. The key stage in the synthetic approach to the DEF ring is the highly stereospecific reaction of 3-benzamido-3,6-dideoxy-l,2-O-isopropylidene-/?-D-arabinohexofurano-5-sulose (8) with organometallic reagents derived from the D-or CD-ring synthon. The synthesis of 8 began with methyl 2,3-anhydro-4,6-O-benzylidene-a-Dmannopyranoside (2), readily available from D-glucose7. The successful trans-diaxial ring opening of oxirane in 2 to 3-azido-3-deoxy-a-D-altropyranoside (3) was achieved by treatment with sodium azide and ammonium chloride in a refluxing mixture of 2-methoxyethanol and water in 82% yield'. Compound 3 was converted into the corresponding 4-benzoate bromide 4 by Hanessian's procedure' in 96% yield. Generation of the alkene 5 from 4 was best achieved by refluxing with l&diazabicyclo[5.4.O]undec-7-ene (DBU) in benzene in 87% yield. The 'H-n.m.r. spectrum of 5 clearly indicates a conformational flip from 4C, (D) to 'C, (D). Selective hydrogenation of the azido group without saturation of the double bond in 5 proved troublesome until we discovered that catalytic hydrogenation with sodim hydrogentelluride (NaTeH)", generated in situ from tellurium and sodium borohydride in ethanol, gave the desired reduction accompanied by migration of the benzoyl group to afford the amino-protect-* Author to whom correspondence should be addressed. ' For an enantiocontrolled synthesis of the ABCD ring see ref. 3. For the synthesis of a new nitro-branched sugar (decironitrose) and 4-0-succinyl+digsnose, see ref. 4. * For partial solutions to this synthesis, see ref. 5. For the total synthesis of nogalamycin congeners, see ref. 6.