54400-75-8Relevant articles and documents
2-Acetamido-2-deoxy-l-iminosugar C-Alkyl and C-Aryl Glycosides: Synthesis and Glycosidase Inhibition
Fontelle, Nathalie,Yamamoto, Arisa,Arda, Ana,Jiménez-Barbero, Jesús,Kato, Atsushi,Désiré, Jér?me,Blériot, Yves
, p. 5477 - 5488 (2018)
The synthesis of a series of six-membered 2-acetamido l-iminosugar C-alkyl and C-aryl glycosides is reported. A diastereoselective sugar-ring enlargement/C-alkylation (or arylation) /ring-contraction sequence applied to d-gluco- and d-manno-configured 2-acetamido azidolactols provides new l-iminosugar C-glycosides. The 1,2-trans stereocontrolled introduction of the pseudoanomeric substituent in these heterocycles strongly suggests a NHAc neighbouring-group participation. In their deprotected form, the nine iminosugars exhibit moderate hexosaminidases and β-glucuronidase inhibition.
Synthesis and biological evaluation of novel doxorubicin-containing ASGP-R-targeted drug-conjugates
Ivanenkov, Yan A.,Majouga, Alexander G.,Petrov, Rostislav A.,Petrov, Stanislav A.,Kovalev, Sergey V.,Maklakova, Svetlana Yu.,Yamansarov, Emil Yu.,Saltykova, Irina V.,Deyneka, Ekaterina V.,Filkov, Gleb I.,Kotelianski, Victor E.,Zatsepin, Timofey S.,Beloglazkina, Elena K.
, p. 503 - 508 (2018/01/02)
Asialoglycoprotein receptor (ASGP-R) belongs to a wide family of C-type lectins and it is currently regarded as an attractive protein in the field of targeted drug delivery (TDD). It is abundantly expressed in hepatocytes and can be found predominantly on the sinusoidal surface especially of HepG2 cells. Therefore, ASGP-R can be used for the TDD of anticancer therapeutics against HCC and molecular diagnostic tools. To date, a variety of mono- and multivalent selective ASGP-R ligands have been discovered. Although many of these compounds have demonstrated a relatively high binding affinity towards the target, the reported synthetic schemes are not handled, complicated and include many non-trivial steps. In the current study, we describe a convenient and versatile synthetic approach to novel monovalent drug-conjugates containing N-acetyl-2-deoxy-2-aminogalactopyranose fragment as an ASGP-R-recognition “core-head” and well-known nonselective cytostatic – Doxorubicin (Dox). This is the first example of the direct conjugation of a drug molecule to the ASGP-targeted warhead by a really convenient manner via a simple linker sequence. The performed MTS-based biological evaluation in HepG2 cells revealed the novel conjugates as having anticancer activity. Confocal microscopy showed that the molecules readily penetrated HepG2 membrane and were mainly localized within the cytoplasm instead of the nucleus. Per contra, Dox under the same conditions demonstrated good anticancer activity and was predominantly concentrated in the nucleus. Therefore, we speculate that the amide “trigger” that we have used in this study for linker attachment is a sufficiently stable inside the cells to be enzymatically or spontaneously degraded. As a consequence, we did not observe the release of the drug. Ligands containing triggers that are more liable towards endogenous hydrolysis within the tissue of targeting are strongly required.
Why Is Direct Glycosylation with N-Acetylglucosamine Donors Such a Poor Reaction and What Can Be Done about It?
Marqvorsen, Mikkel H. S.,Pedersen, Martin J.,Rasmussen, Michelle R.,Kristensen, Steffan K.,Dahl-Lassen, Rasmus,Jensen, Henrik H.
, p. 143 - 156 (2017/04/26)
The monosaccharide N-acetyl-d-glucosamine (GlcNAc) is an abundant building block in naturally occurring oligosaccharides, but its incorporation by chemical glycosylation is challenging since direct reactions are low yielding. This issue, generally agreed upon to be caused by an intermediate 1,2-oxazoline, is often bypassed by introducing extra synthetic steps to avoid the presence of the NHAc functional group during glycosylation. The present paper describes new fundamental mechanistic insights into the inherent challenges of performing direct glycosylation with GlcNAc. These results show that controlling the balance of oxazoline formation and glycosylation is key to achieving acceptable chemical yields. By applying this line of reasoning to direct glycosylation with a traditional thioglycoside donor of GlcNAc, which otherwise affords poor glycosylation yields, one may obtain useful glycosylation results.
