ABSTRACT
Kifunensine is a known inhibitor of type I α-mannosidase enzymes and has been shown to have therapeutic potential for a variety of diseases and application in the expression of high-mannose N-glycan bearing glycoproteins; however, the compound's hydrophilic nature limits its efficacy. We previously synthesized two hydrophobic acylated derivatives of kifunensine, namely, JDW-II-004 and JDW-II-010, and found that these compounds were over 75-fold more potent than kifunensine. Here we explored the effects of these compounds on different mice and human B cells, and we demonstrate that they affected the cells in a similar fashion to kifunensine, further demonstrating their functional equivalence to kifunensine in assays utilizing primary cells. Specifically, a dose-dependent increase in the formation of high-mannose N-glycans decorated glycoproteins were observed upon treatment with kifunensine, JDW-II-004, and JDW-II-010, but greater potency was observed with the acylated derivatives. Treatment with kifunensine or the acylated derivatives also resulted in impaired B-cell receptor (BCR) signaling of the primary mouse B cells; however, primary human B cells treated with kifunensine or JDW-II-004 did not affect BCR signaling, while a modest increase in BCR signaling was observed upon treatment with JDW-010. Nevertheless, these findings demonstrate that the hydrophobic acylated derivatives of kifunensine can help overcome the mass-transfer limitations of the parent compound, and they may have applications for the treatment of ERAD-related diseases or prove to be more cost-effective alternatives for the generation and production of high-mannose N-glycan bearing glycoproteins.
ABSTRACT
Cancer-associated alterations to glycosylation have been shown to aid cancer development and progression. An increased abundance of high mannose N-glycans has been observed in several cancers. Here, we describe the preparation of lectin drug conjugates (LDCs) that permit toxin delivery to cancer cells presenting high mannose N-glycans. Additionally, we demonstrate that cancer cells presenting low levels of high mannose N-glycans can be rendered sensitive to the LDCs by co-treatment with a type I mannosidase inhibitor. Our findings establish that an increased abundance of high mannose N-glycans in the glycocalyx of cancer cells can be leveraged to enable toxin delivery.
Subject(s)
Lectins , Mannose , Mannosidases , Pharmaceutical Preparations , PolysaccharidesABSTRACT
A series of novel spirocyclic DGAT1 inhibitors containing the oxadiazole motif were designed and synthesized for biological evaluation. Several compounds exhibited potent diacylglycerol acyltransferase 1 (DGAT1) inhibitory activity. Optimization of the series led to the identification of five lead compounds 8, 9, 10, 11 and 12 that showed excellent in-vitro activity with IC50 values ranging from 7 to 20 nM against human DGAT1. All compounds demonstrated good druggability as well as microsomal stability and safety profiles such as hERG and CYP. Compound 12 significantly reduced plasma triglyceride levels in-vivo in the mouse model of acute lipid challenge. Significant reduction in plasma TG excursion was observed, thus indicating DGAT1 inhibition in-vivo.
Subject(s)
Carboxylic Acids , Diacylglycerol O-Acyltransferase , Enzyme Inhibitors , Animals , Carboxylic Acids/pharmacology , Diacylglycerol O-Acyltransferase/antagonists & inhibitors , Disease Models, Animal , Drug Design , Enzyme Inhibitors/pharmacology , Mice , Oxadiazoles/pharmacology , TriglyceridesABSTRACT
An engineered cyanovirin-N homologue that exhibits specificity for high mannose N-glycans has been constructed to aid typeâ I α 1,2-mannosidase inhibitor discovery and development. Engineering the lectins C-terminus permitted facile functionalization with fluorophores via a sortase and click strategy. The resulting lectin constructs exhibit specificity for cells presenting high mannose N-glycans. Importantly, these lectin constructs can also be applied to specifically assess changes in cell surface glycosylation induced by typeâ I mannosidase inhibitors. Testing the utility of these lectin constructs led to the discovery of typeâ I mannosidase inhibitors with nanomolar potency. Cumulatively, these findings reveal the specificity and utility of the functionalized cyanovirin-N homologue constructs, and highlight their potential in analytical contexts that require high mannose-specific lectins.
Subject(s)
Lectins/chemistry , Mannosidases/antagonists & inhibitors , Alkaloids/chemistry , Alkaloids/metabolism , Amino Acid Motifs , Aminoacyltransferases/chemistry , Bacterial Proteins/chemistry , Cell Line , Cysteine Endopeptidases/chemistry , Drug Design , Fluorescent Dyes/chemistry , Glycosylation , Humans , Lectins/metabolism , Mannose/chemistry , Mannose/metabolism , Mannosidases/metabolism , Microscopy, FluorescenceABSTRACT
The first "In Water" imidazolecarbonylation of amine is described. A one pot reaction of carbonylimidazolide in water with a nucleophile provides an efficient and general method for the preparation of urea, carbamates and thiocarbamates. Use of an anhydrous solvent and an inert atmosphere could be avoided. Product precipitate out from the reaction mixture and can be obtained in high purity by filtration, resulting in a simple and scalable method.
Subject(s)
Amines/chemistry , Carbamates/chemical synthesis , Imidazoles/chemistry , Thiocarbamates/chemical synthesis , Urea/analogs & derivatives , Urea/chemical synthesis , Water/chemistry , Carbamates/chemistry , Catalysis , Combinatorial Chemistry Techniques , Molecular Structure , Thiocarbamates/chemistry , Urea/chemistryABSTRACT
The first total synthesis of isofregenedadiol, a bicyclic diterpene isolated from H. Viscosum, is reported starting from a D-(-)-pantolactone chiral pool. A one-pot quadruple reaction sequence comprising an enyne ring-closing metathesis/cross-metathesis/Diels-Alder/aromatization for the construction of a target skeleton is the highlight of the present synthesis.
Subject(s)
Diterpenes/chemical synthesis , Cistaceae/chemistry , Diterpenes/chemistry , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , Plants, Medicinal/chemistry , StereoisomerismABSTRACT
An efficient and convenient method for the synthesis of sugar-lactam conjugates is reported starting from readily available sugar azides using the Aubé reaction. Cyclic azido alcohols are used in the Aubé reaction for the first time in a carbohydrate setting. The resulting glycoconjugates could be further used to increase the chemical diversity on the sugar backbone, and may find potential applications as glycomimetics, peptidomimetics, in glycotargeting and in CNS drug delivery.