Swainsonine-related alkaloids

This method was quite sensitive and selective. The detection limit in aqueous solution was 0.75 ng, and from plant material 2.5 ng of castanospermine could be detected. This method was also found to be suitable for the structurally related alkaloids 1-deoxynojirimycin, 1-deoxymannojirimycin, and swainsonine. 

Molyneux, R.J., James, L.F., Panter, K.E. and Ralphs, M.H. (1991b). Analysis and distribution of swainsonine and related polyhydroxyindolizidine alkaloids by thin layer chromatography, Phytochem. Anal., 2, 125-129. 

The only other genus of plants in the Convolvulaceae which has been examined for the presence of calystegines is Ipomoea. Seeds of Weir Vine (Ipomoea sp. Q6 [aff. calobra]) growing in a very limited area of Queensland, Australia were analyzed by GC-MS and shown to contain calystegine B2 (18) and possibly also calystegine C, (21), co-occurring with the potyhydroxyindolizidine alkaloid swainsonine (5). A related species, I. polpha, from the Northern... 

Chemical transformations carried out on the parent alkaloid (-)-162 are surprisingly uncommon when one considers current levels of interest in the therapeutic properties of the compound and its analogs. The stable hydrohalide salts have been described in a patent relating to the compound s antitumor potential 142). Several 2- and 8-0-acyl esters of 162 have been reported 143). The use of the enzyme subtilisin in pyridine permitted selective synthesis of 2-0-butyrylswainsonine (235) from 162 in 23% yield, while catalysis by porcine pancreatic lipase gave 235 (6%) and 1,2-di-O-butyrylswainsonine (236) (31%) 97). Swainsonine has been tethered at C-7 to an agarose matrix for evaluation as an affinity material for mannosidases 144). 

The discovery of the indolizidine alkaloid swainsonine (35) and its A-oxide (37) in the leguminous gtn tdi Astragalus, Oxytropis, and Swainsona suggests a biosynthetic route somewhat resembling those of pyrrolizidine and quinolizidine alkaloid biosynthesis (Harris et al, 1987 Kinghom and Balandrin, 1984). The similarity of certain indolizidine alkaloids to coniine-related compounds, such as 8-coniceine (not naturally occurring) has been observed. 

Fellows, L. E., Castanospermine, swainsonine, and related polyhydroxy alkaloids from plants, Phytochem. Soc. North America, Annual Meeting, 1988. 

Ralphs MH, Creamer R, Baucom D, Gardner DR, Welsh SL, Graham JD, Hart C, Cook D, StegelmeierBL (2008) Relation ship between theendoph5deEmbe// Mspp.andthe toxic alkaloid swainsonine in major locoweed species Astragalus and Oxytropis). J Chem Ecol 34 32-38... 

Two important reviews relate to the synthesis of swainsonine (378) and analogs. In 2000 El Nemr surveyed the many reported syntheses not only of the alkaloid and its stereoisomers, but also of some of its positional isomers and various deoxy and hydroxy analogs. This review includes detailed step-by-step reaction schemes for the unnatural analogs, a luxury that cannot be emulated in the present survey owing to limitations of space. In 2005 Pyne updated El Nemr s review to include syntheses published between 1999 and 2004. ... 

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