Category: 128-09-6

Cao, Ren-Fei; Yu, Lu; Huo, Yu-Xuan; Li, Yao; Xue, Xiao-Song; Chen, Zhi-Min published the artcile< Chiral Lewis Base Catalyzed Enantioselective Selenocyclization of 1,1-Disubstituted Alkenes: Asymmetric Synthesis of Selenium-Containing 4H-3,1-Benzoxazines>, SDS of cas: 128-09-6, the main research area is alkene aryl selenylsuccinimide diphenylphosphinoamino binaphthyl catalyst enantioselective selenocyclization; aryl selenyl benzoxazine preparation.

An enantioselective selenocyclization of 1,1-disubstituted alkenes was achieved for the first time, which was enabled by a novel combination of a chiral BINAM-derived sulfide and an achiral Lewis acid. Various selenium-containing 4H-3,1-benzoxazines, which were widely present in a range of medicinally relevant mols., were readily obtained in moderate to good yields and good to excellent enantioselectivities. A series of tetrasubstituted carbon stereocenters were facilely constructed.

Organic Letters published new progress about Alkenes Role: RCT (Reactant), SPN (Synthetic Preparation), RACT (Reactant or Reagent), PREP (Preparation). 128-09-6 belongs to class chlorides-buliding-blocks, and the molecular formula is C4H4ClNO2, SDS of cas: 128-09-6.

Referemce:
Chloride – Wikipedia,
Chlorides – an overview | ScienceDirect Topics

Demine, Stephane; Garcia Ribeiro, Rita; Thevenet, Julien; Marselli, Lorella; Marchetti, Piero; Pattou, Francois; Kerr-Conte, Julie; Devoogdt, Nick; Eizirik, Decio L. published the artcile< A nanobody-based nuclear imaging tracer targeting dipeptidyl peptidase 6 to determine the mass of human beta cell grafts in mice>, Related Products of 128-09-6, the main research area is beta cell DPP6 nanobody nuclear imaging; Human islet imaging; PET; Pancreatic beta cell imaging; Pancreatic beta cells; SPECT; Type 1 diabetes.

Type 1 diabetes is characterised by a progressive decline in beta cell mass. This is also observed following implantation of pancreatic islet allografts, but there is no reliable information regarding the time course of beta cell loss. This is due to the limited availability of non-invasive pancreatic islet imaging techniques. We have previously described that dipeptidyl peptidase 6 (DPP6) is an alpha and beta cell-specific biomarker, and developed a camelid antibody (nanobody ‘4hD29’) against it. We demonstrated the possibility to detect DPP6-expressing cells by single-photon emission computed tomog. (SPECT)/ computed tomog. (CT), but the correlation between the number of cells grafted and the SPECT signal was not assessed. Here, we investigate whether the 4hD29 nanobody allows us to detect different amounts of human pancreatic islets implanted into immune-deficient mice. In addition, we also describe the adaptation of the probe for use with positron emission tomog. (PET). DPP6 expression was assessed in human samples using tissue arrays and immunohistochem. The effect of the 4hD29 nanobody on cell death and glucose-stimulated insulin secretion was measured in EndoC-βH1 cells and in human islets using Hoechst/propidium iodide staining and an anti-insulin ELISA, resp. We performed in vivo SPECT imaging on severe combined immunodeficient (SCID) mice transplanted with different amounts of EndoC-βH1 cells (2 x 106, 5 x 106 and 10 x 106 cells), human islets (1000 and 3000) or pancreatic exocrine tissue using 99mTc-labeled 4hD29 nanobody. This DPP6 nanobody was also conjugated to N-chlorosuccinimide (NCS)-1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA), radiolabeled with either 67Ga (SPECT) or 68Ga (PET) and used in a proof-of-principle experiment to detect DPP6-expressing cells (Kelly neuroblastoma) grafted in SCID mice. The DPP6 protein is mainly expressed in pancreatic islets. Importantly, the anti-DPP6 nanobody 4hD29 allows non-invasive detection of high amounts of EndoC-βH1 cells or human islets grafted in immunodeficient mice. This suggests that the probe must be further improved to detect lower numbers of islet cells. The 4hD29 nanobody neither affected beta cell viability nor altered insulin secretion in EndoC-βH1 cells and human islets. The conversion of 4hD29 nanobody into a PET probe was successful and did not alter its specificity. These findings suggest that the anti-DPP6 4hD29 nanobody may become a useful tool for the quantification of human islet grafts in mice and, pending future development, islet mass in individuals with diabetes.

Diabetologia published new progress about Allotransplantation. 128-09-6 belongs to class chlorides-buliding-blocks, and the molecular formula is C4H4ClNO2, Related Products of 128-09-6.

Referemce:
Chloride – Wikipedia,
Chlorides – an overview | ScienceDirect Topics

Su, Jinling; Zhang, Yan; Chen, Mingren; Li, Weiming; Qin, Xuewei; Xie, Yanping; Qin, Lixiao; Huang, Shihua; Zhang, Min published the artcile< A Copper Halide Promoted Regioselective Halogenation of Coumarins Using N-Halosuccinimides as Halide Source>, Application In Synthesis of 128-09-6, the main research area is chloro bromo coumarin preparation regioselective; coumarin halogenation halosuccinimide copper halide catalyst.

A safe, convenient, and regioselective synthesis of 3-halo coumarins using a metal halide (CuX2 alone or with ZnX2) promoted halogenation with N-halosuccinimides (NXS) as halide source. The synthesis involved the steady in situ generation of highly reactive pos. halogen (X+) by the coordination of copper or zinc with the N-halosuccinimide and subsequent electrophilic aromatic substitution of the electron-deficient coumarins. This procedure works well also for the halogenation of less electron-rich naphthoquinones, flavones, and methoxypsoralen in moderate to quant. yields. This protocol features simple exptl. conditions using readily available inexpensive reagents and provides a convenient approach to the chlorination or bromination of some useful heteroaromatic compounds

Synlett published new progress about Bromination catalysts (regioselective). 128-09-6 belongs to class chlorides-buliding-blocks, and the molecular formula is C4H4ClNO2, Application In Synthesis of 128-09-6.

Referemce:
Chloride – Wikipedia,
Chlorides – an overview | ScienceDirect Topics

Zakharenko, Alexandra L.; Drenichev, Mikhail S.; Dyrkheeva, Nadezhda S.; Ivanov, Georgy A.; Oslovsky, Vladimir E.; Ilina, Ekaterina S.; Chernyshova, Irina A.; Lavrik, Olga I.; Mikhailov, Sergey N. published the artcile< Inhibition of tyrosyl-DNA phosphodiesterase 1 by lipophilic pyrimidine nucleosides>, Name: 1-Chloropyrrolidine-2,5-dione, the main research area is deoxyribonucleic acid repair nucleoside topoisomerase inhibitor; DNA repair; Tdp1 inhibition; nucleosides; topotecan; tyrosyl-DNA phosphodiesterase.

Inhibition of DNA repair enzymes tyrosyl-DNA phosphodiesterase 1 and poly(ADP-ribose) polymerases 1 and 2 in the presence of pyrimidine nucleoside derivatives was studied here. New effective Tdp1 inhibitors were found in a series of nucleoside derivatives possessing 2′, 3′, 5′ -tri-O-benzoyl-d-ribofuranose and 5-substituted uracil moieties and have half-maximal inhibitory concentrations (IC50) in the lower micromolar and submicromolar range. 2′, 3′, 5′-Tri-O-benzoyl-5-iodouridine manifested the strongest inhibitory effect on Tdp1 (IC50 = 0.6μM). A decrease in the number of benzoic acid residues led to a marked decline in the inhibitory activity, and pyrimidine nucleosides lacking lipophilic groups (uridine, 5-fluorouridine, 5-chlorouridine, 5-bromouridine, 5-iodouridine, and ribothymidine) did not cause noticeable inhibition of Tdp1 (IC50 > 50μM). No PARP1/2 inhibitors were found among the studied compounds (residual activity in the presence of 1 mM substances was 50-100%). Several O-benzoylated uridine and cytidine derivatives strengthened the action of topotecan on HeLa cervical cancer cells.

Molecules published new progress about Antitumor agents. 128-09-6 belongs to class chlorides-buliding-blocks, and the molecular formula is C4H4ClNO2, Name: 1-Chloropyrrolidine-2,5-dione.

Referemce:
Chloride – Wikipedia,
Chlorides – an overview | ScienceDirect Topics

Chang, Chun-Wei; Lin, Mei-Huei; Wu, Chia-Hui; Chiang, Tsun-Yi; Wang, Cheng-Chung published the artcile< Mapping Mechanisms in Glycosylation Reactions with Donor Reactivity: Avoiding Generation of Side Products>, Application In Synthesis of 128-09-6, the main research area is glycosylation thioglycoside mechanism side product formation.

The glycosylation reaction, which is key for the studies on glycoscience, is challenging due to its complexity and intrinsic side reactions. Thioglycoside is one of the most widely used glycosyl donors in the synthesis of complex oligosaccharides. However, one of the challenges is its side reactions, which lower its yield and limits its efficiency, thereby requiring considerable effort in the optimization process. Herein, we reported a multifaceted exptl. approach that reveals the behaviors of side reactions, such as the intermol. thioaglycon transformation and N-glycosyl succinimides, via the glycosyl intermediate. Our mechanistic proposal was supported by low temperature NMR studies that can further be mapped by utilizing relative reactivity values. Accordingly, we also presented our findings to suppress the generation of side products in solving this particular problem for achieving high-yield glycosylation reactions.

Journal of Organic Chemistry published new progress about Glycosylation. 128-09-6 belongs to class chlorides-buliding-blocks, and the molecular formula is C4H4ClNO2, Application In Synthesis of 128-09-6.

Referemce:
Chloride – Wikipedia,
Chlorides – an overview | ScienceDirect Topics