3-Aryl-5-phenyl-(1,2,4)-triazoles were identified as selective inhibitors of 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1). They are active in both in vitro and an in vivo mouse pharmacodynamic (PD) model. The synthesis and structure activity relationships are presented.
View Article and Find Full Text PDFSeveral analogs of 2,3-diaryl pyrroles were synthesized and evaluated as inhibitors of Eimeria tenella cGMP-dependent protein kinase and in in vivo anticoccidial assays. A 4-fluorophenyl group enhances both in vitro and in vivo activities. The most potent analogs are the 5-(N-methyl, N-ethyl, and N-methylazetidine methyl) piperidyl derivatives 12, 23, and 34.
View Article and Find Full Text PDFThe synthesis of a number of indole GnRH antagonists is described. Oxidation of the pyridine ring nitrogen, combined with alkylation at the two position, led to a compound with an excellent in vitro activity profile as well as oral bioavailability in both rats and dogs.
View Article and Find Full Text PDFCarboxyalkyl peptides containing a biphenylylethyl group at the P1' position were found to be potent inhibitors of stromelysin-1 (MMP-3) and gelatinase A (MMP-2), in the range of 10-50 nM, but poor inhibitors of collagenase (MMP-1). Combination of a biphenylylethyl moiety at P1', a tert-butyl group at P2', and a methyl group at P3' produced orally bioavailable inhibitors as measured by an in vivo model of MMP-3 degradation of radiolabeled transferrin in the mouse pleural cavity. The X-ray structure of a complex of a P1-biphenyl inhibitor and the catalytic domain of MMP-3 is described.
View Article and Find Full Text PDFSystematic modification of the C6 acyl side chain of zaragozic acid A, a potent squalene synthase inhibitor, was undertaken to improve its biological activity. Simplification of the C6 side chain to the octanoyl ester has deleterious effects; increasing the linear chain length improves the in vitro activity up to the tetradecanoyl ester. An omega-phenoxy group is a better activity enhancer than an omega-phenyl group.
View Article and Find Full Text PDF(-)-trans-(2S,5S)-2-[3-[(2-Oxopropyl)sulfonyl]-4-n-propoxy-5-(3- hydroxypropoxy)phenyl]-5-(3,4,5-trimethoxyphenyl)tetrahydrofuran (10) is one of the most potent platelet-activating factor (PAF) antagonists in vitro and in vivo developed to date. This diaryltetrahydrofuran derivative evolved from modifications of MK 0287 which has been evaluated in clinical studies for asthma. Two structural modifications of MK 0287 were made: (1) elaboration of the 3'-[(hydroxyethyl)sulfonyl] group to a beta-keto propylsulfonyl, and (2) replacement of the 5'-methyl ether by a 3-hydroxypropyl ether.
View Article and Find Full Text PDF1. The plasma concentration, main route of metabolism and excretion of 3H-L-659,989 were studied in male and female rhesus monkeys by dosing either i.v.
View Article and Find Full Text PDFWe previously reported the isolation of a partial-length human fetal-liver cDNA encoding farnesyl diphosphate (FPP) synthase (EC 2.5.1.
View Article and Find Full Text PDF6-(5-Cholesten-3 beta-yloxy)hexyl 1-thio-beta-D-mannopyranoside (L-644,257) enhances natural host resistance in cyclophosphamide-treated mice against Pseudomonas aeruginosa in a dose-dependent manner. It is active sc, im, and ip but not orally. L-644,257 is substantially more protective against P.
View Article and Find Full Text PDFInt J Immunopharmacol
May 1990
A steroidal glycolipid that enhances the nonspecific cellular response to opportunistic infection in an immunocompromised host has been discovered. A dose dependent response with 6-(5-cholesten-3 beta-yloxy)hexyl 1-thio-beta-D-mannopyranoside, L-644,257, was observed against several infective agents including bacterial, fungal, and viral pathogens in cyclophosphamide-treated mice. A mechanism for this protective action is proposed.
View Article and Find Full Text PDFL-659,989 [trans-2-(3-methoxy-5-methylsulfonyl-4-propoxy-phenyl)-5-(3,4,5- trimethoxyphenyl)tetrahydrofuran] is a p.o. active and extremely potent, selective and competitive platelet-activating factor (PAF) receptor antagonist.
View Article and Find Full Text PDFThe title compound, L-659,989, is a highly potent, competitive, and selective antagonist of the binding of [3H]PAF to its receptors in platelet membranes from rabbits and humans. It exhibits equilibrium inhibition constants for PAF binding of 1.1 nM (rabbit) to 9.
View Article and Find Full Text PDFCinnamyl 1-thio-alpha-D-manno(and L-rhamno)pyranosides have good inhibitory effects in an antigen-specific T cell proliferation assay. The beta anomers are slightly less effective than the alpha anomers. The 6-substituted analogues of cinnamyl 1-thio-alpha-D-mannopyranoside such as 6-deoxy and 6-O-methyl derivatives also block macrophages in presenting the antigen to T cells.
View Article and Find Full Text PDFKadsurenone, a specific receptor antagonist of platelet-activating factor (PAF), and its analogues were prepared from derivatives of cinnamyl alcohol and (allyloxy)phenol. Racemic kadsurenone, resolvable by a Chiralpak column at low temperatures, has an IC50 value of 2 X 10(-7) M, which is about 50% of the activity of the natural product (IC50 = 1 X 10(-7) M). The structural specificity of kadsurenone was further demonstrated by the low PAF-receptor-blocking activities of denudatin B, mirandin A, desallylkadsurenone, and the 2-epimer of kadsurenone.
View Article and Find Full Text PDFHuman placental beta-glucocerebrosidase modified by covalent attachment of N2-(N2, N6-bis [3-(alpha-D-mannopyranosylthio)propionyl]-L- lysyl)-N6-[3-(alpha-D-mannopyranosylthio)propionyl]-L-lysine was administered to rats by intravenous injection. Comparison of enzyme distribution in isolated liver cell populations indicates an increase in enzyme-specific activity of 18-fold in nonparenchymal cells and only 1.5-fold to hepatocytes compared to uninjected control animals.
View Article and Find Full Text PDFThe 6-aminohexyl beta-glycoside of N-acetylmuramyl-L-alanyl-D-isoglutamine and its spacer-arm-linked analog (3.8 nm) were synthesized from 2-methyl-(3,4,6-tri-O-acetyl-1,2-dideoxy-alpha-D-glucopyrano)-[2,1-d]-2- oxazoline, and coupled with meningococcal group C polysaccharide in attempts to enhance the immunogenicity of the polysaccharide antigen.
View Article and Find Full Text PDFSpacer arms 2.1-3.7 nm (21-37 A) long were prepared, and coupled with the methyl beta-glycoside of N-acetylmuramyl-L-alanyl-D-isoglutamine benzyl ester, to give blocked 6-acylates.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
September 1982
The stability and tissue distribution of lipid vesicles modified at the surface by the incorporation of either a galactosyl ceramide (GalCer) or a galactosyl cholesterol (GalChol) glycoconjugate have been studied in mice by measuring the release of vesicle-entrapped 111In. Although the tissue distributions of both vesicle types were similar, the GalCer-containing vesicles were markedly less stable than those prepared with GalChol, whether administered orally or by intraperitoneal injection. Physical characterization of the vesicles in vitro suggests that the increased disruption rate for GalCer vesicles in vivo is related to structural instabilities induced by the cerebroside, which can then result in either an increased rate of vesicle uptake by tissues or a greater susceptibility to lysis.
View Article and Find Full Text PDFVarious numbers of D-mannose residues have been attached via spacer arms to lysine, dilysine, and oligolysine backbones. These D-mannosyl peptide analogues were found to be potent competitive inhibitors of the uptake of 125I-labeled D-mannose-bovine serum albumin conjugate by rat alveolar macrophages. The inhibitory potency of these synthetic ligands increased with increasing number of carbohydrate moieties.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
December 1981
Mammalian macrophages contain a transport system that binds and internalizes glycoproteins with exposed mannose residues. This system and analogous systems on other types of cells require substrates to bear multiple nonreducing terminal residues of the appropriate sugar for effective uptake. Small multivalent synthetic glycopeptides with mannose residues covalently linked through a spacer arm to the alpha- and epsilon-amino groups of lysine, dilysine, and trilysine are competitive inhibitors of rat alveolar macrophage uptake of the neoglycoprotein mannosyl-bovine serum albumin with inhibition constants in the microM range.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
October 1981
Phospholipid vesicles have been extensively investigated because of their usefulness as models for biological membranes and their potential application as carriers for drug delivery. However, preparations of small sonicated vesicles tend to aggregate and fuse (on storage at room temperature and at 4 degrees C), resulting in significant changes in turbidity, rate of uptake by macrophage, and proton NMR linewidths. By modification of the surface of phospholipid vesicles with charged groups such as beta-aminogalactose that extend significantly from the vesicle surface, it is possible to obtain preparations that are stable for greater than 7 days.
View Article and Find Full Text PDFBiochim Biophys Acta
April 1981
Liposomes with synthetic saccharide determinants were prepared from synthetic cholesterol conjugates of D-mannose and 6-amino-6-deoxy-D-mannose and labeled with [51Cr]chromate. The kinetics and tissue distribution of label in mice were determined after footpad and subcutaneous injection. Liposomes bearing either of these saccharide determinants greatly increased retention of label at the injection sites compared to control liposomes, which contain no glycolipid, and to free [51Cr]chromate.
View Article and Find Full Text PDFA group of 1-thio-beta-L-fucopyranosides containing hexadecane, 9-octadecene, adamantane, 1,2-diphenyltetrafluoroethane, and 3-hexynyl- and 3,6-dioxaoctylcholesterols were synthesized as potential immunologic adjuvants. Many of these fucosyl lipids and 6-(5-cholesten-3 beta-yloxy)hexyl 1 thioglycosides were found to give good response to subunit A/Victoria influenza virus. Carbohydrates with L-fucose and D-galactose backbones appeared essential for adjuvant activity.
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