Ethynyl compounds, reaction with sugar

Ethynyl compounds react with sugar lactones to give acetylenic lactols (16,63). Reaction of 2,3-O-isopropylidene-D-ribonolactone (16a) with lithium acetylenic derivatives gave l-(2-substituted ethynyl)-2,3-0-isopropyli-dene-D-ribofuranoses. Similarly, treatment of 2,3 5,6-di-O-isopropylidene-L-gulono-1,4-lactone (9b) with various lithium acetylenic reagents gave... 

Schaffer398 described a synthesis of L-apiose by reaction of 170 with formaldehyde, and Horton et al,373 developed a method for extension of sugar chains through ethynylation of 170 and other aldehydo compounds by the Grignard reaction. 

---