Results 51 to 60 of about 3,309 (181)

Absolute Configurations and Chitinase Inhibitions of Quinazoline-Containing Diketopiperazines from the Marine-Derived Fungus Penicillium polonicum

Marine Drugs, 2020
Three new quinazoline-containing diketopiperazines, polonimides A–C (1–3), along with four analogues (4–7), were obtained from the marine-derived fungus Penicillium polonicum.
Xing-Chen Guo, Ya-Hui Zhang, Wen-Bin Gao, Li Pan, Hua-Jie Zhu, Fei Cao   +5 more
doaj   +1 more source

Prebiotic Organic Chemistry of Diketopiperazines

Asian Journal of Organic Chemistry, Volume 15, Issue 4, April 2026.
Diketopiperazines (DKPs) are considered essential in many life forms, but their prebiotic importance has not been fully understood. This review aims to discuss prebiotic organic chemistry for experimentally and computationally simulated reactions involving DKPs. ABSTRACT Even though the significance of amino acids and polypeptides is well recognized in
Jun Ohata
wiley   +1 more source

Unravelling friction anisotropy by atomic force microscopy

Journal of Microscopy, Volume 302, Issue 1, Page 111-144, April 2026.
Abstract Friction plays a crucial role in both natural phenomena, from the flow of blood cells to earthquakes, and technological applications, from car engines to wind turbines. One of the most fundamental aspects of tribology is friction anisotropy, that is, the dependence of the friction force vector on the direction of sliding.
Clodomiro Cafolla, Marcello Campione
wiley   +1 more source

Synthesis of Peptides, Peptide Nucleic Acid Components, and Other Biogenic Compounds From a Three‐Component Prebiotic Mixture

Chemistry – A European Journal, Volume 32, Issue 9, 2 March 2026.
High‐energy proton irradiation of a formamide–diaminomaleonitrile–glycine system in the presence of meteorites produces a broad spectrum of biogenic compounds, including nucleobases, nucleosides, peptides, and nucleobase–peptide conjugates, highlighting a chemically plausible prebiotic network.
Bruno Mattia Bizzarri, Rosangela Santalucia, Eleonora Mancin, Mikhail Kapralov, Eugene Krasavin, Raffaele Saladino, Ernesto Di Mauro   +6 more
wiley   +1 more source

Pretrichodermamides D–F from a Marine Algicolous Fungus Penicillium sp. KMM 4672

Marine Drugs, 2016
Three new epidithiodiketopiperazines pretrichodermamides D–F (1–3), together with the known N-methylpretrichodermamide B (4) and pretrichodermamide С (5), were isolated from the lipophilic extract of the marine algae-derived fungus Penicillium sp.
Anton N. Yurchenko, Olga F. Smetanina, Elena V. Ivanets, Anatoly I. Kalinovsky, Yuliya V. Khudyakova, Natalya N. Kirichuk, Roman S. Popov, Carsten Bokemeyer, Gunhild von Amsberg, Ekaterina A. Chingizova, Shamil Sh. Afiyatullov, Sergey A. Dyshlovoy   +11 more
doaj   +1 more source

Radical Retrosynthesis of Natural Products Enabled by Iron‐Based Reductive Olefin Coupling

Angewandte Chemie Novit, Volume 2, Issue 1, March 2026.
This review highlights iron‐catalyzed reductive olefin coupling (ROC)—a strategy for C─C bond formation driven by metal‐hydride hydrogen atom transfer (MHAT)—as a key tool in natural products synthesis. This review surveys dozens of total syntheses employing ROC‐based strategies, highlighting its power to forge strained rings, quaternary centers, and ...
Griffin L. Barnes, Alex L. Rerick, Phil S. Baran   +2 more
wiley   +1 more source

Photoisomerization in Cyclic Dipeptide Derivatives: Photoswitchable Supramolecular Hydrogels and the Discovery of Hemipiperazine Photoswitches

ChemPhotoChem, Volume 10, Issue 3, March 2026.
Photoswitchable cyclic dipeptides (CDPs) can be used to prepare hydrogels that reversibly dissipate upon irradiation, or to photomodulate the development of living organisms. We report here applications and perspectives for CDPs containing azobenzene photoswitches or newly discovered hemipiperazine photoswitches in smart materials and biological ...
Zbigniew L. Pianowski
wiley   +1 more source

Halogenated and Nonhalogenated Metabolites from the Marine-Alga-Endophytic Fungus Trichoderma asperellum cf44-2

Marine Drugs, 2018
One new bisabolane sesquiterpene, bisabolan-1,10,11-triol (1), one new norbisabolane sesquiterpene, 12-nor-11-acetoxybisabolen-3,6,7-triol (2), two new naturally occurring monoterpenes, (7S)- and (7R)-1-hydroxy-3-p-menthen-9-oic acids (3 and 4), one new ...
Yin-Ping Song, Feng-Ping Miao, Sheng-Tao Fang, Xiu-Li Yin, Nai-Yun Ji   +4 more
doaj   +1 more source

Comparative Study of the Synthesis and Structural and Physicochemical Properties of Diketopiperazines vs Aza-diketopiperazines

The Journal of Organic Chemistry, 2017
Aza-diketopiperazines (aza-DKPs) represent an underprivileged motif obtained by scaffold hopping of 2,5-diketopiperazines (2,5-DKPs). Herein, we compare the synthesis and the structural and physicochemical properties of aza-DKP 4 vs 2,5-DKP 7. Thus, X-ray and 1H NMR studies show that aza-DKP 4 is a rigid and nonflat scaffold like the 2,5-DKP 7 ...
Regenass, Pierre, Bosc, Damien, Riché, Stéphanie, Gizzi, Patrick, Hibert, Marcel, Karmazin, Lydia, Ganesan, A., Bonnet, Dominique   +7 more
openaire   +5 more sources

Effect of α‐Hydrazino Acids on the Performance of H‐Pro–Pro‐Xaa Catalysts in the Conjugate Addition of Aldehydes to Nitroolefins

ChemistrySelect, Volume 11, Issue 11, 18 March 2026.
The tripeptide Pro‐Pro‐D‐hVal‐OMe, which lacks an acidic group, catalysed the conjugate addition of aldehydes to nitroolefins and afforded γ‐nitroaldehydes in 79–97% yield and 88:14–93:7 e.r. The proposed reaction mechanism relies on the active role of hydrazide NHβ or NHα protons in hydrogen bonding with the reacting species.
Ivona Banović, Ivana Nikšić‐Franjić, Ivanka Jerić   +2 more
wiley   +1 more source