Results 101 to 110 of about 40,506 (345)

Diastereoselective synthesis of some novel benzopyranopyridine derivatives

Beilstein Journal of Organic Chemistry, 2006
BackgroundThe formation of novel N-substituted-1,2,3,4-tetrahydro[1,3]-dioxolo-[6,7]-5H-[1]benzopyrano [3,4-c]pyridines were observed unexpectedly during the acid-mediated ketal removal of ethylenedioxy ketal protected 4-piperidones.
Pradeep K. Mohakhud, Sujeet M. R. Kumar, Vasanth M. R. Kumar, Ravi M. R. Kumar, Moses D. R. Babu, Vyas D. R. K, Om D. R. Reddy   +6 more
doaj   +1 more source

Enantiopure Chiral Crystals: A Powerful Tool for Absolute Asymmetric Synthesis

Asian Journal of Organic Chemistry, EarlyView.
This review covers absolute asymmetric syntheses, which allow the preparation of enantiomerically enriched chiral compounds from achiral precursors. By exploiting the crystallization of certain compounds as a conglomerate, enantiopure chiral crystals are spontaneously obtained.
Jiacheng Li, Valérie Alezra
wiley   +1 more source

4,6‐O‐Phenylboronic Ester Protection for 1,2‐cis‐α‐Selective Glucosylation

Asian Journal of Organic Chemistry, EarlyView.
The 4,6‐O‐phenylboronic ester protection for 1,2‐cis‐α‐selective glucosylation, previously reported by the Crich group, was revisited and the stereodirecting effect of the cyclic protecting group was unveiled. 4,6‐O‐Phenylboronic ester‐protected glucosyl and 2‐azido‐2‐deoxyglucosyl donors exhibited higher α‐selectivity of the glucosylation than the ...
Yuta Umemura, Taro Udagawa, Naoko Komura, Akihiro Imamura, Hideharu Ishida, Hiromune Ando, Hide‐Nori Tanaka   +6 more
wiley   +1 more source

Catalytic Kinetic Resolution of Disubstituted Piperidines by Enantioselective Acylation: Synthetic Utility and Mechanistic Insights.

Journal of the American Chemical Society, 2015
The catalytic kinetic resolution of cyclic amines with achiral N-heterocyclic carbenes and chiral hydroxamic acids has emerged as a promising method to obtain enantio-enriched amines with high selectivity factors.
Benedikt M Wanner, Imants Kreituss, O. Gutierrez, M. Kozlowski, J. Bode   +4 more
semanticscholar   +1 more source

A hepatoprotective experiment on taro vegetable (Colocasia esculenta (L.) Schott) flower employing animal models by mitigating oxidative stress

Animal Models and Experimental Medicine, EarlyView.
The antioxidant efficacy of Colocasia esculenta flower’s methanolic extract was assessed using 2,2′‐azino‐bis‐(3‐ethylbenzothiazoline‐6‐sulfonic) (ABTS) and 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) scavenging assay. The hepatoprotective effect was investigated by assessing liver injury indicators (amino transferase [ALT], aspartate amino transferase [AST],
Mahathir Mohammad, Fahmida Tasnim Richi, Rabiul Hossain, Md. Arafat, Pair Ahmed Jiko, Nazim Uddin Emon, Sayed Al Hossain Rabbi, Tirtha Khastagir, Md. Hemayet Hossain, Safaet Alam   +9 more
wiley   +1 more source

The Synthesis and Biological Activity of 1-Alkyl-4-(3-azacyclobenzoyl)-5-hydroxypyrazole Herbicides

CHIMIA, 2003
The benzoylpyrazoles belong to a class of herbicides that inhibit the enzyme 4-hydroxy-phenylpyruvate dioxygenase (HPPD). This mode of action is characterized by bleaching due to the disruption of plastoquinone and ?-tocopherol biosynthesis ...
Zoltan Benko, Sharon Shinkle, John Van Heertum, Johnny Jackson, Jeffery McQuiston, Jeffery Webster, James Turner, Monte Weimer, Eileen Paterson   +8 more
doaj   +1 more source

Basizität im angeregten Zustand verändert die Selektivität der aromatischen Deuterierung: Anwendung auf die Late‐Stage Markierung von Pharmazeutika

Angewandte Chemie, EarlyView.
Wir präsentieren eine metallfreie Methode für die Deuteriummarkierung von Aromaten in deuteriertem HFIP. Dieser Ansatz nutzt die erhöhte Basizität von Aromaten im angeregten Zustand, um den selektiven Wasserstoffisotopenaustausch an schwer zugänglichen Positionen zu ermöglichen.
Eva Rivera‐Chao, Javier Corpas, Giovanni Lonardi, Volker Derdau, Alessandro Ruffoni, Daniele Leonori   +5 more
wiley   +1 more source

Regio- and Diastereoselective Synthesis of Highly Substituted, Oxygenated Piperidines from Tetrahydropyridines.

Journal of Organic Chemistry, 2015
Diastereoselective epoxidation and regioselective ring-opening methods were developed for the synthesis of densely substituted, oxygenated piperidines from two classes of tetrahydropyridines with distinct stereochemical displays of functionalities. A new
Shuming Chen, B. Mercado, R. Bergman, J. Ellman   +3 more
semanticscholar   +1 more source

Zur Kenntniss der γ‐Halogen‐piperidine [PDF]

, 1898
H. Pauly, C. Harries
openalex   +1 more source

Diastereo- and Enantioselective Iridium Catalyzed Coupling of Vinyl Aziridines with Alcohols: Site-Selective Modification of Unprotected Diols and Synthesis of Substituted Piperidines.

Journal of the American Chemical Society, 2015
The chiral cyclometalated π-allyliridium ortho-C,O-benzoate complex (R)-Ir-VIb derived from [Ir(cod)Cl]2, allyl acetate, 4-cyano-3-nitro-benzoic acid, and (R)-MeO-BIPHEP catalyzes the coupling of N-(p-nitrophenylsulfonyl) protected vinyl aziridine 3a ...
Gang‐Wei Wang, Jana Franke, Chinh Ngo, M. Krische   +3 more
semanticscholar   +1 more source