Deoxy-hydroxylamino-sugar Derivatives and Corresponding Diglycosylnitroxides Radicals SummaryA number of sugar aldonitrones, including C, N-diglycosylnitrones, and ketonitrones have been treated with Grignard reagents or cyanide anion leading to the corresponding deoxy-hydroxylamino-sugars. On oxidation (air, H,IO, or Pb02), these compounds gave the corresponding nitroxide radicals whose ESR. spectra are reported. Analogues of disaccharides, in which the interglycosidic 0-bridge is replaced by a hydroxyirnino group, have been obtained by reacting a partially blocked sugar bearing a free hemiacetal group either with a deoxy-hydroxylarninosugar or with hydroxylamine, followed by reaction with an aldehydosugar and a reducing agent (NaBH4). These reactions represents the key synthetic steps for the oligosaccharide-type synthesis of deoxy-hydroxyimino-oligosaccharides. Their oxidation yielded the corresponding nitroxide radicals whose ESR. spectra gave information on the conformation about the 'interglycosidic' bridge. This type of compounds should constitute useful spin markers for biological studies.A l'exception de deux exemples isoles que nous avons decrits dans une prtcedente communication [4], les analogues de di-ou oligosaccharides dans lesquels le pont oxygene interglycosidique habitue1 est remplacee par un pont hydroxyimino etaient inconnus. Des composes de ce type, de structure proche de celle d'oligosaccharides immunocompetents, devraient &tre appelCs a jouer un r81e important dans la comprehension des mecanismes de reconnaissance cellulaire ou tissulaire. En effet leur facile oxydation en radicaux diglycosylnitroxyde leur permet I ) 2,~~
Synthesis of 3-Deoxy-3-(hydroxyamino)furanose AcetalsReduction of sugar ketoximes with NaBH,CN under acidic conditions constitutes a good synthetic pathway to deoxy(hydroxyamino)sugar derivatives. These compounds which are useful building blocks for the preparation of analogs of various classes of biologically important carbohydrates are reasonably stable.
Derivatives of enose-and ynosephosphonates and related compoundsPreliminary communication SummaryThe gem-dibromo terminal enoses 1 and 7 are convenient sources of glycosylacetylenes which upon reaction with phosphorus electrophiles gave the phosphorusbearing acetylenic sugars 4, 5 and 8. Compounds 5 and 8 underwent cycloaddition reactions leading to isoxazolyl-C-glycosides 6 and 9 respectively. The nitroolefinic sugar derivative 11 gave upon bromination-dehydrobromination the first example of a new kind of potentially useful synthetic intermediates, the gem-bromonitroenose 12. The enosephosphonate 13 was also prepared from 111. The diglycosylhydroxylamine 18 represents another type of phosphorus-bearing acetylenic sugar derivative. Some 'H-and 13C-NMR. data relative to the new tylpes of phosphoruscontaining sugar derivatives synthesized are given.L'activitt anticancereuse de certains accepteurs de Michaei' derivts de sucres [2], de m&me que l'inter&t biologique potentiel de sucres phosphorts qui, de plus, constituent des modeles particulithement riches pour l'ttude par RMN. de couplages a longue distance 31P, l3C et 31P, 'H, nous a amene a prkparer quelques dialkoxyphosphinylenoses et dialkoxyphosphinylynoses ainsi lque des composes apparentes. Nous montrerons ultCrieurement que certains des nouveaux types de dtrives de sucres dkcrits ci-dessous3) sont des intermtdiaires de synthese tres riches.La phosphine 4 (sirop, Sucres phosphores 111; 11: 111. Une communication plus detaillee paraitra ulteneurement. Les analyses dementaires et les donntes spectroscopiques (UV., IR., RMN., SM.) de tous les nouveaux composCs decrits sont en accord avec la structure proposee.[
SummaryNovel types of diglycosyl compounds, some of them bearing a resemblance to natural di-or tri-saccharides are described: a diglycosyldiyne (l), a diglycosylthiophene (2), a diglycosylaziridine (3), a diglycosyldioxolane (4), as well as six C, N-diglycosylnitrones, 9b-9f and 14. These C, N-diglycosylnitrones, on treatment with an acetylenic Grignard reagent, led to the expected acetylenic diglycosylhydroxylamine 11, whereas diglycosylisoxazolines (f. ex. 10) were obtained when these nitrones underwent 1,3-dipolar cycloaddition to acetylenic compounds.Dans la nature, de nombreux oligo-ou polysaccharides jouent des r6les biologiques importants. Ces composes sont constituks d'oses lies entre eux par des liaisons osidiques (acktaliques). L'etablissement entre des unitts d'oses de liaisons autres qu'osidiques, pour former des analogues plus ou moins proclies de disaccharides, voire de trisaccharides, classiques, prtsente un inter& biologicpe evident, d'autant plus marque que certaines des jonctions utilisees, doutes de propriktds tlectrophiles, sont eventuellernent susceptibles de rkagir avec des nuclkophiles biologiques. Nous rapportons ci-dessous la synthese de derives diglycosyliques dans lesquels deux unites d'oses sont likes par deux triples liaisons, une double liaison, une simple liaison ou encore par l'intermtdiaire d'un hetkrocycle.Nous avons anttrieurement decrit [ 11 quelques diglycosyldiynes. Le compose 1 (F. 146,4-147,0", [ u ] g ' = -30,4, c= 1,1, CHC1,) constitue un nouvel exemple de molecule de ce type. Trait& par un hydrogenosulfure alcalin ces diglycosyldiynes conduisent au diglycosylthiophene correspondant, par exemple 2 (sirop, Une communication plus dCtaillCe paraitra ulterieurement.
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