13242-53-0Relevant articles and documents
Determination of the anomeric configurations of 2,3,4,6-tetra-o-acetyl-D- mannopyranosyl azide
Cosgrove, Kelly L.,Bernhardt, Paul V.,Ross, Benjamin P.,McGeary, Ross P.
, p. 473 - 476 (2006)
The structures of 2,3,4,6-tetra-O-acetyl-?-d-mannopyranosyl azide and 2,3,4,6-tetra-O-acetyl-?-d-mannopyranosyl azide were determined using X-ray crystallographic and one-dimensional NOESY techniques. CSIRO 2006.
A biosynthetic pathway for BE-7585A, a 2-thiosugar-containing angucycline-type natural product
Sasaki, Eita,Ogasawara, Yasushi,Liu, Hung-Wen
, p. 7405 - 7417 (2010)
Sulfur is an essential element found ubiquitously in living systems. However, there exist only a few sulfur-containing sugars in nature and their biosyntheses have not been studied. BE-7585A produced by Amycolatopsis orientalis subsp. vinearia BA-07585 has a 2-thiosugar and is a member of the angucycline class of compounds. We report herein the results of our initial efforts to study the biosynthesis of BE-7585A. Spectroscopic analyses verified the structure of BE-7585A, which is closely related to rhodonocardin A. Feeding experiments using 13C-labeled acetate were carried out to confirm that the angucycline core is indeed polyketide-derived. The results indicated an unusual manner of angular tetracyclic ring construction, perhaps via a Baeyer-Villiger type rearrangement. Subsequent cloning and sequencing led to the identification of the bex gene cluster spanning ～30 kbp. A total of 28 open reading frames, which are likely involved in BE-7585A formation, were identified in the cluster. In view of the presence of a homologue of a thiazole synthase gene (thiG), bexX, in the bex cluster, the mechanism of sulfur incorporation into the 2-thiosugar moiety could resemble that found in thiamin biosynthesis. A glycosyltransferase homologue, BexG2, was heterologously expressed in Escherichia coli. The purified enzyme successfully catalyzed the coupling of 2-thioglucose 6-phoshate and UDP-glucose to produce 2-thiotrehalose 6-phosphate, which is the precursor of the disaccharide unit in BE-7585A. On the basis of these genetic and biochemical experiments, a biosynthetic pathway for BE-7585A can now be proposed. The combined results set the stage for future biochemical studies of 2-thiosugar biosynthesis and BE-7585A assembly.
Design, Synthesis, biological investigations and molecular interactions of triazole linked tacrine glycoconjugates as Acetylcholinesterase inhibitors with reduced hepatotoxicity
Ahmed, Ajaz,Bhagat, Kavita,Choudhary, Sushil,Kaur Gulati, Harmandeep,Kumar, Ajay,Kumar, Nitish,Mukherjee, Debaraj,Singh Bedi, Preet Mohinder,Singh, Atamjit,Singh, Harbinder,Vir Singh, Jatinder
, (2021/11/23)
Tacrine is a known Acetylcholinesterase (AChE) inhibitors having hepatotoxicity as main liability associated with it. The present study aims to reduce its hepatotoxicity by synthesizing tacrine linked triazole glycoconjugates via Huisgen's [3 + 2] cycloaddition of anomeric azides and terminal acetylenes derived from tacrine. A series of triazole based glycoconjugates containing both acetylated (A-1 to A-7) and free sugar hydroxyl groups (A-8 to A-14) at the amino position of tacrine were synthesized in good yield taking aid from molecular docking studies and evaluated for their in vitro AChE inhibition activity as well as hepatotoxicity. All the hybrids were found to be non-toxic on HePG2 cell line at 200 μM (100 % cell viability) as compared to tacrine (35 % cell viability) after 24 h of incubation period. Enzyme kinetic studies carried out for one of the potent hybrids in the series A-1 (IC50 0.4 μM) revealed its mixed inhibition approach. Thus, compound A-1 can be used as principle template to further explore the mechanism of action of different targets involved in Alzheimer's disease (AD) which stands as an adequate chemical probe to be launched in an AD drug discovery program.
Synthesis of malformin-A1, C, a glycan, and an aglycon analog: Potential scaffolds for targeted cancer therapy
Andreana, Peter R.,Hossain, Farzana,Nishat, Sharmeen
, (2022/02/21)
Improvement in therapeutic efficacy while reducing chemotherapeutic side effects remains a vital objective in synthetic design for cancer treatment. In keeping with the ethos of therapeutic development and inspired by the Warburg effect for augmenting biological activities of the malformin family of cyclic-peptide natural products, specifically anti-tumor activity, a β-glucoside of malformin C has been designed and synthesized utilizing precise glycosylation and solution phase peptide synthesis. We optimized several glycosylation procedures utilizing different donors and acceptors. The overarching goal of this study was to ensure a targeted delivery of a glyco-malformin C analog through the coupling of D-glucose moiety; selective transport via glucose transporters (GLUTs) into tumor cells, followed by hydrolysis in the tumor microenvironment releasing the active malformin C a glycon analog. Furthermore, total synthesis of malformin C was carried out with overall improved strategies avoiding unwanted side reactions thus increasing easier purification. We also report on an improved solid phase peptide synthesis protocol for malformin A1.
Synthesis of podophyllotoxin-glycosyl triazoles via click protocol mediated by silver (I)-N-heterocyclic carbenes and their anticancer evaluation as topoisomerase-II inhibitors
Nerella, Srinivas,Kankala, Shravankumar,Gavaji, Brahmeshwari
supporting information, p. 9 - 16 (2019/06/27)
Herein we report the regioselective synthesis of podophyllotoxin-Glycosyl triazole hybrids catalysed by Ag(I)-N-heterocyclic carbene (Ag(I)-NHC) in a short reaction time (～30 min) at ambient conditions. In principle, it is the first report of Click alkyne-azide cycloaddition catalysed by Ag(I)-NHC catalyst and moreover, this new methodology yielded good results when compared with traditional CuAAC in terms of reaction time and selectivity. The synthesised compounds were further explored for in vitro anticancer activity against four human cancer cell lines Du145, HeLa, A-549, and MCF-7 and found that these synthesised compounds possess significant anticancer activity. Further, the compounds 5a and 5e were identified as promising leads due to their better activity across all cell lines than that of the standard drug etoposide. Molecular docking studies of 5a & 5e with DNA Topoisomerase-II were revealed that the free energy calculations of active compounds were in good agreement with observed IC50 values.
