A practical synthesis of kifunensine analogues as inhibitors of endoplasmic reticulum alpha-mannosidase I.
[reaction: see text] A practical synthesis of the potent class I alpha-mannosidase inhibitor kifunensine (1) beginning from the inexpensive and readily available starting material L-ascorbic acid (15) is described. The protected amino-alcohol ((2R,3R,4R,5R)-5-amino-2,3:4,6-diisopropylidenedioxyhexanol, 11) served as a key intermediate from which several N-1 substituted kifunensine analogues (including N-methyl, N-cyclohexyl, and N-bis(hydroxymethyl)methyl) and 2-desoxakifunensine analogues (including N-H and N-methyl) were prepared and screened for inhibition of human endoplasmic reticulum alpha-mannosidase I (ER Man I) and mouse Golgi alpha-mannosidase IA (Golgi Man IA). In addition, several pseudodisaccharide kifunensine analogues in which a mannose residue was tethered to N-1 of kifunensine via a two-, three-, or four-carbon linker and an affinity-bound kifunensine analogue were also prepared and evaluated for biological activity. While the synthesized N-1 kifunesine analogues were found to be less potent inhibitors of Class I alpha-mannosidases than kifuensine itself, the bis(hydroxymethyl)methylkifunensine analogue 6 was shown to selectively inhibit ER Man I over Golgi Man IA.
Hering
Kirk W
KW
Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109-1055, USA.
Karaveg
Khanita
K
Moremen
Kelley W
KW
Pearson
William H
WH
D000470:Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D006801:Humans; D008361:Mannosidases / Q000037:antagonists & inhibitors*; D008968:Molecular Conformation; D013237:Stereoisomerism; D013329:Structure-Activity Relationship
D000470:Alkaloids; D004791:Enzyme Inhibitors; D008361:Mannosidases; C065629:kifunensine; C568343:MAN1B1 protein, human