Keto

Studies of complex systems and emerging properties to mimic biosystems are at the forefront of chemical research. Dynamic multistep cascades, especially those exhibiting allosteric regulation, are challenging. Herein, we demonstrate a versatile platform of photoswitchable covalent cascades toward remote and bidirectional control of reversible covalent bonds and ensuing assemblies. The relay of a photochromic switch, keto-enol equilibrium, and ring-chain equilibrium allows light-mediated reversible allosteric structural changes...

Since the 2000s, an increasing number of new psychoactive substances have appeared on the illicit drug market. β-keto-arylcyclohexylamine compounds play important pharmacological roles in anesthesia; however, because these new psychoactive substances have rapidly increasing illicit recreational use, the lack of detailed toxicity data are of particular concern. Therefore, analysis of their metabolites can help forensic personnel provide references and suggestions on whether a suspect has taken an illicit new psychoactive β-keto-arylcyclohexylamine...

Invasive fungal infections are a significant public health concern, with mortality rates ranging from 20% to 85% despite current treatments. Therefore, we examined whether a ketogenic diet could serve as a successful treatment intervention in murine models of Cryptococcus neoformans and Candida albicans infection in combination with fluconazole-a low-cost, readily available antifungal therapy. The ketogenic diet is a high-fat, low-carbohydrate diet that promotes fatty acid oxidation as an alternative to glycolysis through the production of ketone bodies...

Described is a new synthetic route to bis(2-hydroxy-3,5-di-t-butylphenyl)methanone and its derivatives. The combined esterification/photo-Fries rearrangement approach enables a modular preparation of keto-bridged polyphenols. This protecting group-free process is highly atom- and step-economic, and a scalable production was easily achieved in the continuous-flow mode.

We experienced four cases of high-risk metastatic castration-sensitive prostate cancer (mCSPC) in which first-line treatment with abiraterone showed a sustained long-term response of over 5 years. We conducted immunohistochemical staining of aldo-keto reductase family 1 member C3 (AKR1C3) expression, which associate with poor prognosis of metastatic castration-resistant prostate cancer (mCRPC), and all prostate cancer tissue from four cases showed negative. These results suggested that AKR1C3-negative high-risk mCSPC cases may respond well to first-line treatment with abiraterone...

The α-keto acid dehydrogenase complex (KDHc) class of mitochondrial enzymes is composed of four members: pyruvate dehydrogenase (PDHc), α-ketoglutarate dehydrogenase (KGDHc), branched-chain keto acid dehydrogenase (BCKDHc), and 2-oxoadipate dehydrogenase (OADHc). These enzyme complexes occupy critical metabolic intersections that connect monosaccharide, amino acid, and fatty acid metabolism to Krebs cycle flux and oxidative phosphorylation (OxPhos). This feature also imbues KDHc enzymes with the heightened capacity to serve as platforms for propagation of intracellular and intercellular signaling...

Although identical in molecular formula and weight, curcumin and cyclocurcumin show remarkable differences in their reactivity. Both are natural compounds isolated from the rhizome of turmeric, the former is involved in the diketo/keto-enol tautomerism through the bis-α,β-unsaturated diketone unit according to the polarity of the solvent, while the latter could react by trans - cis isomerization due to the presence of the α,β-unsaturated dihydropyranone moiety. Even if curcumin is generally considered responsible of the therapeutical properties of Curcuma longa L...

Deoxynivalenol (DON), primarily generated by Fusarium species, often exists in agricultural products. It can be transformed to 3- epi -deoxynivalenol (3- epi -DON), with a relatively low toxicity, via two steps. DDH in Pelagibacterium halotolerans ANSP101 was proved to convert DON to 3-keto-deoxynivalenol (3-keto-DON). In the present research, AKR4, a NADPH-dependent aldo/keto reductase from P. halotolerans ANSP101, was identified to be capable of converting 3-keto-DON into 3- epi -DON. Our results demonstrated that AKR4 is clearly a NADPH-dependent enzyme, for its utilization of NADPH is higher than that of NADH...

The relationship between the chemical structures of six flavonoids and their abilities to inhibit the formation of polycyclic aromatic hydrocarbons (PAHs) in a heated meat model system was investigated. The PAH8 forming in samples was analyzed by using QuEChERS coupled GC-MS. Inhibitory effects of PAHs were myricetin (72.1%) > morin (55.7%) > quercetin (57.3%) > kaempferol (49.9%) > rutin (32.7%) > taxifolin (30.2%). The antioxidant activities of these flavonoids, assessed through (1, 1-diphenyl-2-picrylhydrazyl) free radical scavenging activity assay (DPPH), [2,2'-azinobis (3-ethylbenzothiazoline-6-sulphonic acid)] free radical scavenging activity assay (ABTS) and ferric ion reducing antioxidant power assay (FRAP) assays, exhibited a significant negative correlation with PAH reduction...

By co-culturing two endophytic fungi (Chaetomium virescens and Xylaria grammica) collected from the medicinal and edible plant Smilax glabra Roxb. and analyzing them with MolNetEnhancer module on GNPS platform, seven undescribed chromone-derived polyketides (chaetoxylariones A-G), including three pairs of enantiomer ones (2a/2b, 4a/4b and 6a/6b) and four optical pure ones (1, 3, 5 and 7), as well as five known structural analogues (8-12), were obtained. The structures of these new compounds were characterized by NMR spectroscopy, single-crystal X-ray diffraction, 13 C NMR calculation and DP4+ probability analyses, as well as the comparison of the experimental electronic circular dichroism (ECD) data...

As cancer continues to be the leading cause of death worldwide, additional therapeutic options other than traditional platinum-based chemotherapy have become available that target tumor cells in innovative ways. Immunotherapies (e.g., immune checkpoint inhibitors (ICI)) ramp up the immune system to target cancer cells, providing patients with more personalized and tumor cell-specific treatment options. This new age oncological treatment option has been found to provide a more meaningful and stronger alternative to traditional chemotherapy, resulting in longer periods of remission and milder side effects...

An effective method by high-speed countercurrent chromatography coordinated with silver nitrate for the preparative separation of sterones and triterpenoid saponins from Achyranthes bidentata Blume was developed. Methyl tert-butyl ether/n-butanol/acetonitrile/water (4:2:3:8, v/v/v/v) was selected for 20-hydroxyecdysone (compound 1), chikusetsusaponin IVa methyl ester (compound 4), 2'-glycan-11-keto-pigmented saponin V (compound 5), as well as a pair of isomers of 25S-inokosterone (compound 2) and 25R-inokosterone (compound 3), which were further purified by silver nitrate coordinated high-speed countercurrent chromatography...

Five new cytochalasins, diaporchalasins A-E (1-5), together with 14 known congeners (6-19) were isolated from the endophytic fungus Diaporthe sp. BMX12, which was isolated from the branches of Aquilaria sinensis. The structures of the new compounds were elucidated by extensive spectroscopic analyses including high-resolution electron spray ionization mass spectrometry (HRESIMS) and nuclear magnetic resonance (NMR). Their absolute configurations were assigned by theoretical electronic circular dichroism (ECD) calculations...

Oxaloacetic acid (OAA) is a β-ketocarboxylic acid, which plays an important role as an intermediate in some metabolic pathways, including the tricarboxylic acid cycle, gluconeogenesis and fatty acid biosynthesis. Animal studies have indicated that supplementing oxaloacetic acid shows an increase of lifespan and other substantial health benefits including mitochondrial DNA protection, and protection of retinal, neural and pancreatic tissues. Most of the chemical transformations of OAA in the metabolic pathways have been extensively studied; however, the understanding of decarboxylation of OAA at the atomic level is relatively lacking...

Asymmetric sulfonylation from a reaction of cyclopropan-1-ol, sulfur dioxide, and 1-(alkynyl)naphthalen-2-ol in the presence of a catalytic amount of organocatalyst at room temperature is developed. Axially chiral ( S )-( E )-1-(1-(alkylsulfonyl)-2-arylvinyl)naphthalen-2-ols are generated in moderate to good yields with excellent enantioselectivity and regioselectivity under mild conditions. During this transformation, γ-keto sulfinate generated in situ from cyclopropan-1-ol and sulfur dioxide acts as the key intermediate...

BACKGROUND: Existing treatments for primary dysmenorrhoea (PD), such as NSAIDs, impart side effects. Ge-Gen decoction (GGD), a traditional Chinese medicine, has shown promise in treating PD, but its exact mechanisms remain unclear. Here, we aimed to investigate the efficiency of GGD in alleviating PD using a rat model to understand its precise mechanism of action. METHODS: We established a rat model of dysmenorrhoea induced by oestradiol and oxytocin. The PD rats were administered GGD or Ibuprofen (positive control) intragastrically once daily for seven consecutive days...

Fusarium head blight (FHB) and the presence of mycotoxin deoxynivalenol (DON) pose serious threats to wheat production and food safety worldwide. DON, as a virulence factor, is crucial for the spread of FHB pathogens on plants. However, germplasm resources that are naturally resistant to DON and DON-producing FHB pathogens are inadequate in plants. Here, detoxifying bacteria genes responsible for DON epimerization were used to enhance the resistance of wheat to mycotoxin DON and FHB pathogens. We characterized the complete pathway and molecular basis leading to the thorough detoxification of DON via epimerization through two sequential reactions in the detoxifying bacterium Devosia sp...

Fucosylation is facilitated by converting GDP-mannose to GDP-4-keto-6-deoxymannose, which GDP-mannose 4,6-dehydratase, a crucial enzyme in the route, carries out. One of the most prevalent glycosylation alterations linked to cancer has reportedly been identified as fucosylation. There is mounting evidence that GMDS is intimately linked to the onset and spread of cancer. Furthermore, the significance of long-chain non-coding RNAs in the development and metastasis of cancer is becoming more well-recognized, and the regulatory mechanism of lncRNAs has emerged as a prominent area of study in the biological sciences...

Two glycosyltransferase genes belonging to UGT88 family were identified to have 6'-deoxychalcone 4'-glucosyltransferase activity in dahlia. 6'-Deoxychalcones (isoliquiritigenin and butein) are important pigments for yellow and orange to red flower color. 6'-Deoxychalcones are glucosylated at the 4'-position in vivo, but the genes encoding 6'-deoxychalcone 4'-glucosyltransferase have not yet been identified. In our previous study, it was indicated that snapdragon (Antirrhinum majus) chalcone 4'-O-glucosyltransferase (Am4'CGT) has isoliquiritigenin 4'-glucosylation activity...

The asymmetric cross-coupling of unsaturated bonds, hampered by their comparable polarity and reactivity, as well as the scarcity of efficient catalytic systems capable of diastereo- and enantiocontrol, presents a significant hurdle in organic synthesis. In this study, we introduce a highly adaptable photochemical cobalt catalysis framework that facilitates chemo- and stereoselective reductive cross-couplings between common aldehydes with a broad array of carbonyl and iminyl compounds, including N -acylhydrazones, aryl ketones, aldehydes, and α-keto esters...