Galantins

An elegant total synthesis of the semiprotected form of lincosamine was realized by Marshall and Beaudoin [116]. An aldehyde derived from destomic acid (6-amino-6-deoxy-L-g/yc ro-D-ga/acto-heptonic acid) was derived in a similar way from a L-serinal derivative via hetero Diels-Alder addition to 1-ethoxy-3-[(trimethylsilyl)oxy]-4-benzyloxy-1,3-butadiene [142]. A similar method was applied to the preparation of a semiprotected form of anhydrogalantinic acid, a component of the antibiotic galantin I [142]. 

Sakai, N., and Ohfune, Y., Efficient synthesis of the revised structure of (-)-galantinic acid. Tetrahedron Lett., 31, 4151, 1990. 

The cis-isomeric alkenes gave all four possible isomers." The galantinic add derivative 56 was obtained from an L-serinal derivative in seven steps induding two chain-extension reactions." ... 

C7H15NO5 193.199 Formerly represented as cyclic anhydro ether. Struct, revised to acyclic form in 1990. Constit. amino acid of Galantin I. Cryst. (MeOH aq.). 

Ethyl 2,3-dideoxy-a-D-pentofuranoside, D-705 Ethyl 2,3-dideoxy-p-D-pentofuranoside, D-705 Galantinic acid, G-212 Isoinosine 2-Deoxy, 1-52... 

Isomerization of the double bond out of conjugation (to give 5.257) followed by treatment with base gave lactone 6.268. Introduction of the p-hydroxyl group in 6.269 led to the final product, (-)-galantinic acid (6-amino-3,5,7-trihydroxyheptanoic acid, 6.270). ... 

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