Methyl (2′S,3′S)-3,4-O-(2′,3′-dimethoxybutane-2′,3′-diyl)-α-l-rhamnopyranoside: a glycosyl acceptor
نویسندگان
چکیده
The title compound, C(13)H(24)O(7), is the product of the ketalization of methyl l-(+)-rhamnopyran-oside with 2,3-butane-dione. It crystallizes with two mol-ecules in the asymmetric unit, which are connected by O-H⋯O hydrogen bonds. The C-3,4 diequatorial hydroxy groups of the methyl l-(+)-rhamnopyran-oside were protected, leaving the C-2 hydroxy group free. The l-(+)-rhamnopyran-oside and 2',3'-dimethoxy-butane-2',3'-diyl rings adopt chair conformations and all meth-oxy groups are in axial positions. The absolute configuration was assumed from the synthesis.
منابع مشابه
3,4-O-(2,3-Dimethoxybutane-2,3-diyl)-S-(4-methylphenyl)-1-thia-α-d-mannopyranoside
In the title mol-ecule, C(19)H(28)O(7)S, the six-membered manno-pyran-oside and dioxane rings both display typical chair conformations. In the crystal structure, the hydr-oxy groups are involved in inter-molecular hydrogen bonds, which link the mol-ecules into chains extended along the b axis.
متن کاملSynthesis of the Oligosaccharides Related to Branching Sites of Fucosylated Chondroitin Sulfates from Sea Cucumbers
Natural anionic polysaccharides fucosylated chondroitin sulfates (FCS) from sea cucumbers attract great attention nowadays due to their ability to influence various biological processes, such as blood coagulation, thrombosis, angiogenesis, inflammation, bacterial and viral adhesion. To determine pharmacophore fragments in FCS we have started systematic synthesis of oligosaccharides with well-de...
متن کاملEfficient synthesis of building blocks for branched rhamnogalacturonan I fragments.
Starting from allyl 2-O-acetyl-3-O-benzyl-α-l-rhamnopyranoside (3), allyl (2,3,4,6-tetra-O-benzoyl-β-d-galactopyranosyl)-(1→4)-2-O-acetyl-3-O-benzyl-α-l-rhamnopyranoside (5) was synthesized under Helferich conditions. Module 5 was converted to 2,3,4,6-tetra-O-benzoyl-β-d-galactopyranosyl-(1→4)-2-O-acetyl-3-O-benzyl-α-l-rhamnopyranosyl bromide (8) which was then coupled with methyl (allyl 2,3-di...
متن کامل(E)-3,3′-(Diazene-1,2-diyl)bis(1-methyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-5-ium) dinitrate dihydrate
The title compound, C(12)H(18)N(8) (2+)·2NO(3) (-)·2H(2)O, was synthesized unexpectedly from 3-amino-1-methyl-1,4,5,6-tetra-hydro-pyrrolo-[3,4-c]pyrazol-5-ium chloride and cerium(IV) ammonium nitrate. The cation has a crystallographically imposed centre of symmetry. In the crystal, the ions and water mol-ecules are linked via O-H⋯N, N-H⋯O and O-H⋯O hydrogen bonds into a three-dimensional network.
متن کاملPolythiazide
The crystal structure of the title compound, C(11)H(13)ClF(3)N(3)O(4)S(3) (systematic name: 6-chloro-2-methyl-3-{[(2,2,2-trifluoro-eth-yl)sulfan-yl]meth-yl}-3,4-dihydro-2H-1,2,4-benzothia-diazine-7-sul-f-on-amide 1,1-diox-ide; CRN: 346-18-9), exhibits a two-dimensional network of hydrogen-bonded mol-ecules parallel to (01). The NH and NH(2) groups act as donor sites and the sulfonyl O atoms as ...
متن کامل