17609-48-2Relevant academic research and scientific papers
Enantioselective carbene insertion into the N-H bond of benzophenone imine
Yang, Jian,Ruan, Peiran,Yang, Wei,Feng, Xiaoming,Liu, Xiaohua
, p. 10305 - 10309 (2019)
Efficient enantioselective insertion of α-diazoesters into the N-H bond of N-sp2-hybridized benzophenone imine was realized by using Rh2(esp)2 and chiral guanidine cooperative catalysis. Both aliphatic and aromatic substituted α-amino esters were obtained in high yields (up to 99%) and good enantioselectivities (up to 95.54.5 er) under mild reaction conditions.
Diastereoselective synthesis of aliphatic α,α-difluoro- β3-amino esters via a sonocatalyzed Reformatsky reaction
March, Taryn L.,Johnston, Martin R.,Duggan, Peter J.
supporting information; experimental part, p. 182 - 185 (2012/02/16)
(R)-2-Phenylglycine ethyl ester was found to be a cheap and effective auxiliary for the preparation of aliphatic α,α-difluoro- β3-amino esters via a Reformatsky reaction performed under sonication conditions. The products were obtained in good to high yield and ≥96:4 dr, thus providing a new stereoselective route to this under-represented class of compounds. A facile one-pot removal of the phenylglycine moiety and concomitant Boc protection subsequently afforded the corresponding Boc-protected β3-amino esters in excellent yield.
Asymmetric synthesis of α-amino acids by reduction of N-tert-butanesulfinyl ketimine esters
Reddy, Leleti Rajender,Gupta, Aditya P.,Liu, Yugang
experimental part, p. 3409 - 3415 (2011/06/25)
A highly regio- and diastereoselective reduction of various N-tert-butanesulfinyl ketimine esters with L-Selectride resulting in the formation of α-amino acids is reported. This method is quite general and also practical for the preparation of both enantiomers of aryl or aliphatic α-amino acids in high yields.
Asymmetric synthesis of protected arylglycines by rhodium-catalyzed addition of arylboronic acids to N-tert-butanesulfinyl imino esters
Beenen, Melissa A.,Weix, Daniel J.,Ellman, Jonathan A.
, p. 6304 - 6305 (2007/10/03)
A new method for the Rh(I)-catalyzed addition of arylboronic acids to N-tert-butanesulfinyl imino esters has been developed for the asymmetric synthesis of arylglycine derivatives. This method provides high yields (61-90%) and diastereoselectivities (>98:2) for a variety of functionalized arylboronic acids. The N-sulfinyl arylglycine ester products are versatile intermediates for further transformations, including selective protecting group removal, conversion to β-amino alcohols, and direct incorporation into peptides. Copyright
Reversal of multiple drug resistance in cholangiocarcinoma by the glutathione S-transferase-π-specific inhibitor O 1-hexadecyl-γ-glutamyl-S-benzylcysteinyl-D-phenylglycine ethylester
Nakajima, Takaharu,Takayama, Tetsuji,Miyanishi, Koji,Nobuoka, Atsushi,Hayashi, Tsuyoshi,Abe, Tomoyuki,Kato, Junji,Sakon, Kiyoyuki,Naniwa, Yoshimitsu,Tanabe, Hirohumi,Niitsu, Yoshiro
, p. 861 - 869 (2007/10/03)
Cholangiocarcinoma is markedly resistant to chemotherapy and has a dismal prognosis, but its mechanism of drug resistance is unknown. This study examines whether glutathione S-transferase-π (GSTP1-1) is involved in resistance to anticancer drugs in cholangiocarcinoma and whether GSTP1-1-specific inhibitors can overcome this resistance. First, immunohistochemical examination disclosed strong staining of all our 17 cholangiocarcinoma specimens for GSTP1-1, irrespective of histological type. Transfection of the GSTP1-1 antisense expression vector into a human cholangiocarcinoma cell line (HuCCT1) apparently decreased its intracellular GSTP1-1 concentration, and the sensitivity of transfectants to adriamycin (ADR), cisplatin, and alkylating agents such as melphalan and 4-hydroxyperoxycyclophosphamide (4-HC) was increased significantly, compared with that of mock transfectants. We next synthesized GSTP1-1-specific inhibitors by elongating the carbon chain of the ethylester at the N-terminal of γ-glutamyl-S-benzylcysteinyl-phenylglycyl diethylester and performed a pharmacokinetic study on them. Of six GSTP1-1 inhibitors tested, O1-hexadecyl-γ-glutamyl-S-benzylcysteinyl-D-phenylglycine ethylester (C16C2) showed the smallest volume of central compartment and smallest volume of distribution at steady state and the second smallest clearance, being the most effective inhibitor in vivo. The IC50 value of ADR or 4-HC for HuCCT1 cells decreased greater by treatment with C16C2 in a dose-dependent manner, paralleling the decrease in GSTP1-1 activity, than that of ADR or 4-HC alone. The antitumor activity of ADR or cyclophosphamide was clearly enhanced by combination therapy with C16C2 in a xenograft model. In conclusion, our results demonstrated that GSTP1-1 is a resistance factor for anticancer drugs in cholangiocarcinoma and that C16C2, a GSTP1-1-specific inhibitor, is a potent agent against the resistance.
Synthesis of α-phenyl-1-(R)-(-)-piperidineacetic esters
Juarez, Jorge,Gnecco, Dino,Galindo, Alberto,Enriquez, Raul G.,Marazano, Christian,Reynolds, William F.
, p. 203 - 206 (2007/10/03)
Several α-phenyl-1-(R)-(-)-piperidineacetic esters 3(a-e), were obtained in pure enantiomeric form by condensing (R)-(-)-α-phenylglycine esters 2(a-e) with 1,5-dibromopentane. Similarly, (R)-(-)-α-phenylglycine esters, 2(a-e), were prepared from (R)-(-)-α-phenylglycine 1 with high yields.
