Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.23 (beta-galactosidase)
 14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Condensation of 2-S-(2,3,4,6-tetra-O-acetyl-beta-D-galactopyranosyl)-2- thiopseudourea hydrobromide with 2,3,6-tri-O-benzoyl-4-O-trifluoromethylsulfonyl-beta-D-galactopyra nosyl- (1-->1)-(2S,3R,4E)-3-O-benzoyl-2-dichloroacetamido-4-octa decen-1,3-diol afforded S-(2,3,4,6-tetra-O-acetyl-beta-D-galactopyranosyl)-(1-->4)-2,3,6-tri-O- benzoyl-4-thio-beta-D-glucopyranosyl-(1-->1)-(2S,3R,4E)-3-O-benzoy l-2- dichloroacetamido-4-octadecen-1,3-diol in good yield. Removal of the protecting groups, followed by selective N-acylation of the sphingosine amino group with either a fluorescent or a radioactive fatty acid, gave labeled lactosylceramide analogues in good yield. Since these products contained a beta-thioglycosidic bond between the two sugar moieties, they were totally resistant to the action of acid lysosomal glycosidases. Likewise, condensation of 2-S-(2,3,4,6-tetra-O-acetyl-beta-D-glucopyranosyl)-2- thiopseudourea hydrobromide and 2,3,4,6-tetra-O-acetyl-beta-D-galactopyranosyl-(1-->4)-2,3,6- tri-O-acetyl-1-S-acetyl-1-thio-beta-D-glucopyranose with (2R,3R,4E)-3-O-benzoyl-2-dichloroacetamido-1-iodo-4-octad ecen-3-ol in methanolic sodium acetate afforded the corresponding beta-thioglycosides 14 and 16, respectively, in good yield. These beta-thioglycosides were converted into glucosylceramide and lactosylceramide analogues following removal of the protecting groups and by subsequent selective N-acylation using either a fluorescent or adioactive fatty acid N-succinimidyl ester. Whereas the glucosylthioceramides thus obtained proved to be completely undegradable by lysosomal glucocerebrosidase, the lactosylceramides containing the beta-thioglycosidic bond between the lactose and the ceramide residues could be degraded by lysosomal GM1-beta-galactosidase to give the corresponding glucosylthioceramides. These compound did not yield to any further enzymatic degradation.
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PMID:Synthesis of fluorescent and radioactive analogues of two lactosylceramides and glucosylceramide containing beta-thioglycosidic bonds that are resistant to enzymatic degradation. 854 3

To develop a novel nonviral gene carrier, three types of polyamine-dialkyl phosphates conjugates were synthesized via an unprecedented synthetic intermediate, dimerized dicetyl phosphate (DCP) anhydride, and the transfection efficiency and the complexation properties of the conjugate-DNA were evaluated. Condensation of DCP by 1,3,5-triisopropylbenzenesulfonyl chloride, TPSCl, gives the dimerized anhydride, which is stable enough to isolate by column chromatography in approximately 90% yield. The anhydride is reactive with various amines, i.e., spermidine, spermine, and polyethylenimine (PEI(1800)), providing corresponding polyamine-DCP conjugates via phosphoramidate linkage. The polyamine-DCP conjugates exhibited moderate transfection efficacy evaluated by beta-galactosidase assay. The conjugate-DNA complex was observed by using an atomic force microscope (AFM), revealing that the PEI(1800)-DCP conjugate, which showed the most efficient transfection, enables the formation of the more compact complex with DNA.
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PMID:Novel polyamine-dialkyl phosphate conjugates for gene carriers. Facile synthetic route via an unprecedented dialkyl phosphate. 1526 70