China
Africa
Explore chapters and articles related to this topic
Biocatalytic Reduction of Organic Compounds by Marine-Derived Fungi
Published in Se-Kwon Kim, Marine Biochemistry, 2023
Gabriel S. Baia, David E. Q. Jimenez, André Luiz Meleiro Porto
The ERs most used in research is the OYE family of flavin oxidoreductases (EC 1.6.99.1). These enzymes can catalyze the asymmetric reduction of α,β-unsaturated alkenes in a ping-pong bi-bi mechanism. The hydride transfer from the nicotinamide moiety of NAD(P)H to the enzyme-bound flavin occurs in a reductive half-reaction. When oxidized to NAD(P)+, the transfer of the hydride ion from the reduced flavin to the alkene takes place in an oxidative half-reaction [13]. The alkene is bound to the active site of the enzyme by hydrogen- bonding via His/His or His/Asn amino acid interaction, which enhances the C=C bond polarization and supports the hydride transfer from FMNH2 to the C-β of the alkene [13]. Proton transfer occurs simultaneously from the Tyr amino acid residue of the opposite side and completes the reduction reaction in Figure 15.5.
Crocus sativus and the Prized Commodity, Saffron
Published in Raymond Cooper, Jeffrey John Deakin, Natural Products of Silk Road Plants, 2020
Jeffrey John Deakin, Raymond Cooper
Terpenes are a huge and varied class of hydrocarbons that make up a majority of plant resins and saps. Terpenes are made up of multiples of isoprene molecules. Isoprene is an alkene having the molecular formula, CH2:C(CH3).CH:CH2, which has two carbon–carbon double bonds within a short five-carbon chain.
Chemistry of Essential Oils
Published in K. Hüsnü Can Başer, Gerhard Buchbauer, Handbook of Essential Oils, 2020
Ethylene provides a good example of a petrochemical feedstock for the synthesis of lipids and polyketides. It can be oligomerized to provide a variety of alkenes into which functionalization can be introduced by hydration, oxidation, hydroformylation, and so on. Of course, telomerization can be used to provide functionalized materials directly.
Linkers in fragment-based drug design: an overview of the literature
Published in Expert Opinion on Drug Discovery, 2023
Dylan Grenier, Solène Audebert, Jordane Preto, Jean-François Guichou, Isabelle Krimm
Other short aliphatic linkers were reported in the case of fragment dimerization, i.e., where two identical fragments binding to separate chains of an oligomeric target are linked, taking advantage of the spatial proximity of the binding pockets. Fragment dimerization was successfully applied to inhibitors targeting the oligomeric form of the pyruvate kinase M2 [13]. Owing to the proximity of the amide moieties of the fragments, linking of the fragments required a simple methylene group. The dimerization reaction was carried out by activating DMSO with DCMT. The best activator molecule showed an AC50 of 3 nM. Similarly, the dimerization of a fragment bound to the AMPA receptor was published [14]. The authors used a Grubbs reaction to join the two identical fragments. The alkene-containing molecule was then reduced to a two-carbon aliphatic chain, resulting in a 13.4 nM ligand.
Composition of aerosols from thermal degradation of flavors used in ENDS and tobacco products
Published in Inhalation Toxicology, 2022
Philip J. Kuehl, Jacob D. McDonald, Derek T. Weber, Andrey Khlystov, Matthew A. Nystoriak, Daniel J. Conklin
Eugenol (4-allyl-2-methoxyphenol) is the main constituent of several essential oils of clove (Bhuiyan et al. 2010). The primary degradation products of eugenol were vanillin (4-hydroxy-3-methoxybenzaldehyde), 2,4-dimethylbenzoic acid and 2-3 ring PAHs (naphthalene and acenathylene). Notably, eugenol is often used as a precursor of vanillin through chemical or biotransformation, and thus, vanillin formation was unsurprising. In fact, isomerization of eugenol double bond and oxidation of isoeugenol is described (Lampman et al. 1977). Additional constituents result from the oxidation and aromatization. High temperature formed vanillin and benzene as well as low molecular weight VOCs (e.g. formaldehyde and acetaldehyde). Volatile aromatic organics were produced in similar concentrations by high and low temperature, but these were more minor constituents compared with the low molecular weight alkenes and alkanes.
Small Molecule Inhibitors of Programmed Cell Death Ligand 1 (PD-L1): A Patent Review (2019–2021)
Published in Expert Opinion on Therapeutic Patents, 2022
Jingjing Deng, Zhengqi Cheng, Juyang Long, Alexander Dömling, Micky Tortorella, Yuanze Wang
To obtain good affinity toward the PD-L1 dimer it is well known that the biphenol core is important, but the linker also play an important role by connecting and allowing the aryl and tail groups sitting in the proper position where they could form stronger interactions with nearby amino acid residues. Therefore, some other linkers have been explored by different companies. Maxinovel Pharma has filed several patents that adopt the alkene as the linker instead of ether. (Figure 7) [38–41] From the compounds they disclosed, 18 and 19 showed an IC50 of 2.3 and 2.9 nM in the in vitro PD-1/PD-L1 binding assay, respectively. In addition, compound 19 also inhibited cell-based PD-1/PD-L1 binding with an EC50 of 808.8 nM. More importantly, one of the compounds (MAX-10181) has entered phase I clinical trials although the exact structure has not yet been disclosed. (NCT04122339)