100938-55-4Relevant academic research and scientific papers
Activation of glycosyl trichloroacetimidates with perchloric acid on silica (HClO4-SiO2) provides enhanced α-selectivity
Ludek, Olaf R.,Gu, Wenlu,Gildersleeve, Jeffrey C.
, p. 2074 - 2078 (2010)
Obtaining high stereoselectivity in glycosylation reactions is often challenging in the absence of neighboring group participation. In this study, we demonstrate that activation of glycosyl trichloroacetimidate donors with immobilized perchloric acid on s
Synthetic and immunological studies on trimeric MUC1 immunodominant motif antigen-based anti-cancer vaccine candidates
Li, Mingjing,Yu, Fan,Yao, Chao,Wang, Peng George,Liu, Yonghui,Zhao, Wei
, p. 993 - 999 (2018)
Therapeutic vaccines have been regarded as a very promising treatment modality against cancer. Tumor-associated MUC1 is a promising antigen for the design of antitumor vaccines. However, body's immune tolerance and low immunogenicity of MUC1 glycopeptides
A Synthetic MUC1 Glycopeptide Bearing βGalNAc-Thr as a Tn Antigen Isomer Induces the Production of Antibodies against Tumor Cells
Leiria Campo, Vanessa,Riul, Thalita B.,Oliveira Bortot, Leandro,Martins-Teixeira, Maristela B.,Fiori Marchiori, Marcelo,Iaccarino, Emanuela,Ruvo, Menotti,Dias-Baruffi, Marcelo,Carvalho, Ivone
, p. 527 - 538 (2017/03/22)
This study presents the synthesis of the novel protected O-glycosylated amino acid derivatives 1 and 2, containing βGalNAc-SerOBn and βGalNAc-ThrOBn units, respectively, as mimetics of the natural Tn antigen (αGalNAc-Ser/Thr), along with the solid-phase assembly of the glycopeptides NHAcSer-Ala-Pro-Asp-Thr[αGalNAc]-Arg-Pro-Ala-Pro-Gly-BSA (3-BSA) and NHAcSer-Ala-Pro-Asp-Thr[βGalNAc]-Arg-Pro-Ala-Pro-Gly-BSA (4-BSA), bearing αGalNAc-Thr or βGalNAc-Thr units, respectively, as mimetics of MUC1 tumor mucin glycoproteins. According to ELISA tests, immunizations of mice with βGalNAc-glycopeptide 4-BSA induced higher sera titers (1:320 000) than immunizations with αGalNAc-glycopeptide 3-BSA (1:40 000). Likewise, flow cytometry assays showed higher capacity of the obtained anti-glycopeptide 4-BSA antibodies to recognize MCF-7 tumor cells. Cross-recognition between immunopurified anti-βGalNAc antibodies and αGalNAc-glycopeptide and vice versa was also verified. Lastly, molecular dynamics simulations and surface plasmon resonance (SPR) showed that βGalNAc-glycopeptide 4 can interact with a model antitumor monoclonal antibody (SM3). Taken together, these data highlight the improved immunogenicity of the unnatural glycopeptide 4-BSA, bearing βGalNAc-Thr as Tn antigen isomer.
Stereoselective synthesis of natural and non-natural thomsen-nouveau antigens and hydrazide derivatives
Shaik, Ahmad Ali,Nishat, Sharmeen,Andreana, Peter R.
supporting information, p. 2582 - 2585 (2015/06/16)
A selective glycosylation strategy enabling access to all stereochemical combinations of tumor associated Thomsen-nouveau (Tn) antigen, d-GalNAc-O-Ser/Thr, has been developed. The key component for selectivity is the phthalimide-protected d- or l-amino acid acceptors which allow access to α- or β-anomers in excellent yields (72-96%) and selectivity (～100%) when appropriate C-2 substitution is installed. The glycoamino acid intermediates were divergently converted to Tn-based carboxylates or to hydrazides by tandem Pd-C debenzylation followed by treatment with hydrazine hydrate or hydrazine hydrate treatment alone.
α-Selective glycosylation affords mucin-related GalNAc amino acids and diketopiperazines active on Trypanosoma cruzi
Martins-Teixeira, Maristela B.,Campo, Vanessa L.,Biondo, Monica,Sesti-Costa, Renata,Carneiro, Zumira A.,Silva, Jo?o S.,Carvalho, Ivone
, p. 1978 - 1987 (2013/05/08)
This work addresses the synthesis and biological evaluation of glycosyl diketopiperazines (DKPs) cyclo[Asp-(αGalNAc)Ser] 3 and cyclo[Asp-(αGalNAc)Thr] 4 for the development of novel anti-trypanosomal agents and Trypanosoma cruzi trans-sialidase (TcTS) inhibitors. The target compounds were synthetized by coupling reactions between glycosyl amino acids αGalNAc-Ser 7 or αGalNAc-Thr 8 and the amino acid (O-tBu)-Asp 17, followed by one-pot deprotection-cyclisation reaction in the presence of 20% piperidine in DMF. The protected glycosyl amino acid intermediates 7 and 8 were, in turn, obtained by α-selective, HgBr2-catalysed glycosylation reactions of Fmoc-Ser/Thr benzyl esters 12/14 with αGalN3Cl 11, being, subsequently, fully deprotected for comparative biological assays. The DKPs 3 and 4 showed relevant anti-trypanosomal effects (IC50 282-124 μM), whereas glycosyl amino acids 1 and 2 showed better TcTS inhibition (57-79%) than the corresponding DKPs (13-25%).
Iodine-mediated glycosylation en route to mucin-related glyco-aminoacids and glycopeptides
Kaerkkaeinen, Tiina S.,Ravindranathan Kartha,MacMillan, Derek,Field, Robert A.
, p. 1830 - 1834 (2008/12/21)
The use of iodine-DDQ as a promoter for glycosylation of Fmoc-Ser-OBn and Fmoc-Thr-OBn with phenylseleno 3,4,6-tri-O-acetyl-2-azido-2-deoxy-α-d-galactopyranoside in toluene-dioxane gave 49% and 73% yields, respectively, of the corresponding α-glycosides as the sole glycoside products. Reductive acetylation of the azide groups and cleavage of the benzyl esters by hydrogenolysis gave building blocks that were used in solid-phase synthesis to prepare triglycosylated tetrapeptides (Ac3GalNAc-α-Ser)3-Gly and (Ac3GalNAc-α-Thr)3-Gly in 27% and 49% overall yield, respectively.
Iodine promoted glycosylation with glycosyl iodides: α-glycoside synthesis
Van Well, Renate M.,Kartha, K. P. Ravindranathan,Field, Robert A.
, p. 463 - 474 (2007/10/03)
Glycosidation of fully acetylated glucopyranosyl iodide with methanol under the influence of iodine gave α-glucoside selectively. Use of less reactive acceptors led to the formation of α/β-mixtures. Glycosylations with fully benzoylated glucosyl iodide yielded β-glucosides only. In contrast, iodine-promoted glycosylation of serine and threonine with 2-azido-2-deoxy-glycosyl iodides, easily obtained in three steps, proceeded smoothly, resulting in only α-linked products in high yield in most cases. Copyright Taylor & Francis, Inc.
Highly efficient stereospecific preparation of Tn and TF building blocks using thioglycosyl donors and the Ph2SO/Tf2O promotor system
Cato, David,Buskas, Therese,Boons, Geert-Jan
, p. 503 - 516 (2007/10/03)
The activation of 2-azido-2-deoxy Tn and TF thioglycosyl donors by the powerful thiophilic promoter system Ph2SO/Tf2O has been investigated. Glycosylation of an Fmoc-protected threonine derivative gave 1,2-cis glycosides in high yiel
Synthetic and immunological studies on clustered modes of mucin-related Tn and TF O-linked antigens: The preparation of a glycopeptide-based vaccine for clinical trials against prostate cancer
Kuduk, Scott D.,Schwarz, Jacob B.,Chen, Xiao-Tao,Glunz, Peter W.,Sames, Dalibor,Ragupathi, Govindaswami,Livingston, Philip O.,Danishefsky, Samuel J.
, p. 12474 - 12485 (2007/10/03)
The syntheses of two tumor-associated carbohydrate antigens, Tn and TF, have been achieved using glycal assembly and cassette methodologies. These synthetic antigens were subsequently clustered (c) and immunoconjugated to a carrier protein (KLH or BSA) or
