Results 111 to 120 of about 13,199 (173)

Synthesis of tricyclic fused pyrrolidine nitroxides from 2-alkynylpyrrolidine-1-oxyls

Beilstein Journal of Organic Chemistry
Rotational correlation time is a key parameter for organic radical contrast agents (ORCA) for magnetic resonance imaging (MRI). Design of polycyclic systems with incorporated nitroxide moieties in which rotation of the radical separately from the ...
Mark M. Gulman, Yuliya F. Polienko, Sofia Yu. Trakhininа, Yuri V. Gatilov, Tatyana V. Rybalova, Sergey A. Dobrynin, Igor A. Kirilyuk   +6 more
doaj   +1 more source

Saturating mutagenesis on the Ser118 residue responsible for the spectral tuning mechanism of the orange/green‐reversible cyanobacteriochrome AM1_1499g1

Plant Biology, EarlyView.
This graphical abstract illustrates our systematic site‐saturation mutagenesis at the Ser118 position of the AM1_1499g1 GAF domain. By replacing this single residue, we generated a diverse array of variants with distinct spectral properties, demonstrating the remarkable molecular plasticity of cyanobacteriochromes and their customizability for ...
A. Yoneda, T. Suzuki, R. Narikawa
wiley   +1 more source

Direct Access to Chiral Piperidines by Enantioselective HAT‐Initiated C(sp3)─H Oxidation

Angewandte Chemie, Volume 138, Issue 44, 26 October 2026.
The direct desymmetrization of piperidines is achieved through manganese‐catalyzed enantioselective α‐C(sp3)─H oxidation with hydrogen peroxide, affording versatile chiral N,O‐acetals in good yields and with high enantio‐ and diastereoselectivity. These intermediates provide access to diverse functionalized piperidines with retention of chirality ...
Sethuraman Muthuramalingam, Josep M. Luis, Arnau Call, Quentin Lefebvre, Matthew S. Sigman, Miquel Costas   +5 more
wiley   +2 more sources

Polyglycine Strands Within a Collagen Triple Helix

Biopolymers, Volume 117, Issue 6, November 2026.
ABSTRACT The collagen triple helix is the most abundant protein structural motif in animals. It tolerates any amino acid in its Xaa and Yaa positions but demands glycine (Gly) at every third position, where the residue packs into the sterically forbidding core of the triple helix and donates the recurring interstrand N–H⋯OC hydrogen bond that stitches
Wasin Tiarawut, Gabriel Saenz, Jinyi Yang, Ronald T. Raines   +3 more
wiley   +1 more source

1,4‐Brook Rearrangement of β‐Silyl Allylic Alcohols: Trisubstituted Alkenes by Copper‐Mediated Stereoretentive ipso‐Substitution Reactions

Angewandte Chemie, Volume 138, Issue 44, 26 October 2026.
To fully leverage the power of the ruthenium‐catalyzed trans‐hydrosilylation of propargyl alcohols, it was necessary to develop a practical and robust method for the activation of those products that carry the silyl group distal to the hydroxy substituent.
Paul Haf‐Moths, Jack L. Sutro, Alois Fürstner   +2 more
wiley   +2 more sources

synthesis of bipyrrole-pyrrolidine

, 2008
Polyamide containing groove binding agents have been widely reported. We synthesized pyrrolidine to displace one of pyrrole of distamycin, and research into structure which was effected by optical and saturated ...
Lin, Chun-yu
core  

Biomimetic Approach toward the Total Synthesis of rac-2-(Acylmethylene)pyrrolidine Alkaloids

, 2015
2-(Acylmethylene)­pyrrolidine derivatives were synthesized via intermolecular decarbonylative Mannich reaction from various methyl ketones and 1-alkyl-1-pyrroliniums, generated in situ from 1-alkylprolines.
Pei-Hua Tsai (1554214), Yuandong Jhong (1574905), Chih-Wei Chang (182136), Yun-Chung Chen (1574902), Chia-Chun Hsu (1574899), Tun-Cheng Chien (1574893), Yu-Chiao Shih (1574896)   +6 more
core   +1 more source

Salicylic Acid as a Food‐Derived Bioactive Constituent of Tiaoqi Daozhi Decoction: A Potential Functional Food Ingredient to Restoring Gut Barrier Function in Constipation‐Predominant IBS

Food Science &Nutrition, Volume 14, Issue 11, November 2026.
Tiaoqi Daozhi Decoction (TQDZD) is a classic formulation composed of eight medicine‐food homologous botanicals. UPLC‐MS/MS profiling identified 1962 non‐redundant compounds in its aqueous extract, predominantly phenolic acids and flavonoids, of which 107 metabolites were systemically bioavailable.
Min Duan, Lixia Huang, Yingyue Xu, Ya Huang, Xiaojun Yang   +4 more
wiley   +1 more source

Sustainable Access to N‐Heterocycles: One‐Pot Cascade Synthesis of Pyrroles From Bio‐Derived Furans

Angewandte Chemie, Volume 138, Issue 44, 26 October 2026.
Highly dispersed platinum (Pt) clusters on Brønsted acid‐rich HY zeolite enable a one‐pot cascade conversion of bio‐derived furans and nitroarenes into pyrroles. Highly dispersed Pt sites ensure selective nitro hydrogenation, while Pt nanoparticles promote undesired over‐hydrogenation.
Haifeng Qi, Germán López Robledo, Jianglin Duan, Yujing Ren, Kathrin Junge, Matthias Beller   +5 more
wiley   +2 more sources

Punigratane, a novel pyrrolidine alkaloid from Punica granatum rind with putative efflux inhibition activity

, 2016
A new pyrrolidine alkaloid named Punigratane was isolated from the rind of Punica granatum. This is the first report of a pyrrolidine-like structure from the rind.
Zumaana Rafiq (2328160), Rosy Vennila (2328166), Sreevidya Narasimhan (2328169), Rama Vaidyanathan (2328163)   +3 more
core   +1 more source