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Homocubane, a highly strained cage hydrocarbon, contains two very different positions for the introduction of a nitrogen atom into the skeleton, e. g. a position 1 exchange results in a tertiary amine whereas position 9 yields a secondary amine. Herein reported is the synthesis of 9‐azahomocubane along with associated structural characterization, physical property analysis and chemical reactivity. Not only is 9‐azahomocubane readily synthesized, and found to be stable as predicted, the basicity of the secondary amine was observed to be significantly lower than the structurally related azabicyclo[2.2.1]heptane, although similar to 1‐azahomocubane. [ABSTRACT FROM AUTHOR]

Using computational methods and chemical intuition, the proposed structure of janthinolide A is shown to be incorrect. It is further shown that the material described as janthinolide A is highly likely to be janthinolide C. [ABSTRACT FROM AUTHOR]

Pirfenidone, an oral anti‐fibrotic and anti‐inflammatory medication used for the treatment of idiopathic pulmonary fibrosis (IPF), has been proposed to treat post‐COVID pneumonia pulmonary fibrosis (PF). However, pirfenidone displays side effects which include hepatotoxicity and anorexia. Cubane and cyclooctatetraene (COT) derivatives of pirfenidone were prepared as bioisostere/biomotif replacements of the phenyl ring to explore potential changes in activity. The key intermediate, aminocubane, enabled the synthesis of both the cubane and cyclooctatetraene (COT) derived pirfenidone analogues in 6 steps. The COT derivative was observed to display similar activity and cytotoxicity with pirfenidone in an anti‐virus and ACE2 inhibition assay, although limited effect was observed from pirfenidone and the analogues described herein. [ABSTRACT FROM AUTHOR]

6-(Methylsulfinyl)hexyl isothiocyanate (6-MSITC) has several biological functions. The present study aimed to evaluate the composition of hydroponically grown Tasmanian wasabi (Eutrema japonicum (Miq.) Koidz.) for 6-MSITC in all plant tissues and investigate the influence of wasabi (rhizome and stem blend) in high-carbohydrate, high-fat (H) diet-fed rats. Male Wistar rats were fed either a corn starch (C) or H diet. After the initial 8 weeks, half of the animals on the C and H diets were given 5% (w/w) wasabi powder in their respective diets for an 8-week duration (CW and HW). The control animals received diets without supplementation throughout the 16-week experiment. Our findings demonstrated that wasabi grown under hydroponic conditions contained 6-MSITC in all parts of the plant such as the stem, leaf and flower, as well as the commonly used rhizome, albeit at lower concentrations. Rats treated with wasabi showed reductions in body weight (H, 460.0 ± 9.5; HW, 416.0 ± 3.6 g), fat mass (H, 178 ± 14; HW, 120 ± 23 g), plasma triglycerides (H, 1.7 ± 0.3; HW, 0.9 ± 0.3 mmol/L) and total cholesterol (H, 1.5 ± 0.1; HW, 1.0 ± 0.04 mmol/L), and the plasma activities of aspartate transaminase. Systolic blood pressure and the area under the curve of blood glucose concentration were decreased by wasabi treatment. Thus, wasabi may be a novel alternative treatment to assist in the management of obesity and related metabolic disorders. [ABSTRACT FROM AUTHOR]

A 2-azabicyclo[4.2.0]octa-4,7-diene derivative was unexpectedly isolated from the photochemical irradiation of 2-vinyl-1,2-dihydropyridine. A cascading 6π–8π–4π electrocyclic rearrangement has been proposed as a possible mechanistic pathway. Herein disclosed is the isolation of the 2-azabicyclo[4.2.0]octa-4,7-diene skeleton derived from the photochemical irradiation of 2-vinyl-1,2-dihydropyridine. A cascading 6π–8π–4π electrocyclic rearrangement is proposed as the mechanistic rationale. This is the first observation of this ring system. [ABSTRACT FROM AUTHOR]

Natural products continue to be reported at an astonishing rate from a wide range of multidisciplinary research activities in the pursuit of understanding the chemistry of biodiversity. However, the elucidation of chemical structure in the modern era is heavily reliant on the analysis and interpretation of multiple spectroscopic outputs, and in most cases this activity is by no means trivial. Structural errors continue to be described given the inherent complexity of natural products. Computer‐Assisted Structure Elucidation (CASE) continues to provide improved resolving power in this regard, but for enhanced accuracy quantum chemical spectrum prediction methodology is paramount. Reported herein are a range of counterfactual natural products, identified through chemical principal screening, which have been reassigned using a combination of chemical intuition, chemical synthesis, CASE and DU8+ spectrum prediction. [ABSTRACT FROM AUTHOR]

Herbicides are commonly deployed as the front-line treatment to control infestations of weeds in native ecosystems and among crop plants in agriculture. However, the prevalence of herbicide resistance in many species is a major global challenge. The specificity and effectiveness of herbicides acting on diverse weed species are tightly linked to targeted proteins. The conservation and variance at these sites among different weed species remain largely unexplored. Using novel genome data in a genome-guided approach, 12 common herbicide-target genes and their coded proteins were identified from seven species of Weeds of National Significance in Australia: Alternanthera philoxeroides (alligator weed), Lycium ferocissimum (African boxthorn), Senecio madagascariensis (fireweed), Lantana camara (lantana), Parthenium hysterophorus (parthenium), Cryptostegia grandiflora (rubber vine), and Eichhornia crassipes (water hyacinth). Gene and protein sequences targeted by the acetolactate synthase (ALS) inhibitors and glyphosate were recovered. Compared to structurally resolved homologous proteins as reference, high sequence conservation was observed at the herbicide-target sites in the ALS (target for ALS inhibitors), and in 5-enolpyruvylshikimate-3-phosphate (EPSP) synthase (target for glyphosate). Although the sequences are largely conserved in the seven phylogenetically diverse species, mutations observed in the ALS proteins of fireweed and parthenium suggest resistance of these weeds to ALS-inhibiting and other herbicides. These protein sites remain as attractive targets for the development of novel inhibitors and herbicides. This notion is reinforced by the results from the phylogenetic analysis of the 12 proteins, which reveal a largely consistent vertical inheritance in their evolutionary histories. These results demonstrate the utility of high-throughput genome sequencing to rapidly identify and characterize gene targets by computational methods, bypassing the experimental characterization of individual genes. Data generated from this study provide a useful reference for future investigations in herbicide discovery and development. [ABSTRACT FROM AUTHOR]

UbiA prenyltransferase domain‐containing protein‐1 (UBIAD1) is responsible for the biosynthesis of menaquinone‐4 (MK‐4), a cofactor for extrahepatic carboxylation of vitamin K‐dependent (VKD) proteins. Genetic variations of UBIAD1 are mainly associated with Schnyder corneal dystrophy (SCD), a disease characterized by abnormal accumulation of cholesterol in the cornea. Results from in vitro studies demonstrate that SCD‐associated UBIAD1 mutations are defective in MK‐4 biosynthesis. However, SCD patients do not exhibit typical phenotypes associated with defects of MK‐4 or VKD carboxylation. Here, we coupled UBIAD1's biosynthetic activity of MK‐4 with VKD carboxylation in HEK293 cells that stably express a chimeric VKD reporter protein. The endogenous Ubiad1 gene in these cells was knocked out by CRISPR‐Cas9‐mediated genome editing. The effect of UBIAD1 mutations on MK‐4 biosynthesis and VKD carboxylation was evaluated in Ubiad1‐deficient reporter cells by determining the production of MK‐4 or by measuring the efficiency of reporter‐protein carboxylation. Our results show that the hot‐spot mutation N102S has a moderate impact on MK‐4 biosynthesis (retained ˜ 82% activity) but does not affect VKD carboxylation. However, the G186R mutation significantly affected both MK‐4 biosynthesis and VKD carboxylation. Other mutations exhibit varying degrees of effects on MK‐4 biosynthesis and VKD carboxylation. These results are consistent with in vivo results obtained from gene knock‐in mice and SCD patients. Our findings suggest that UBIAD1's MK‐4 biosynthetic activity does not directly correlate with the phenotypes of SCD patients. The established cell‐based assays in this study provide a powerful tool for the functional studies of UBIAD1 in a cellular milieu. [ABSTRACT FROM AUTHOR]

Unusual polyenols that defied chemical principles were reassigned as the nucleosides, adenosine and uridine, using a combination of chemical intuition underpinned by Computer Assisted Structure Elucidation (CASE) and DFT methods. [ABSTRACT FROM AUTHOR]

Tandem oxidative-dehydrogenation of primary alcohols to give α,β-unsaturated aldehydes in one pot are rare transformations in organic synthesis, with only two methods currently available. Reported herein is a novel method using the bench-stable salt methyltriphenylphosphonium perruthenate (MTP3), and a new co-oxidant NEMO·PF6 (NEMO = N -ethyl- N -hydroxymorpholinium) which provides unsaturated aldehydes in low to moderate yields. The Ley-Griffith oxidation of (hetero)arylated primary alcohols with N -oxide co-oxidants NMO (NMO = N -methylmorpholine N -oxide)/NEMO, is expanded by addition of the N -oxide salt NEMO·PF6 to convert the intermediate saturated aldehyde into its unsaturated counterpart. The discovery, method development, reaction scope, and associated challenges of this method are highlighted. The conceptual value of late-stage dehydrogenation in natural product synthesis is demonstrated via the synthesis of a polyene scaffold related to auxarconjugatin B. A novel method is described, using perruthenate salts, for performing the rarely reported dehydrogenation of primary alcohols to afford unsaturated aldehydes in low to moderate yields. The discovery, method development, reaction scope, and associated challenges of this method are presented in detail. [ABSTRACT FROM AUTHOR]

Cubane, a hexahedral hydrocarbon, can be converted into an asymmetric molecule with a minimum of three substituents. The resulting chiral cubane can be used as a pharmacophore or a chiral ligand. Starting from the cubane carboxamide, the 1,2,3‐substituted compound was synthesized by sequential ortho‐metalation. The 1,3,5‐substituted compound was synthesized by combining site‐selective halogenation and halogen‐metal exchange and the resulting racemate was subjected to enantiomeric resolution by HPLC. [ABSTRACT FROM AUTHOR]