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Here, we report a three-step concise and stereoselective synthesis route to one of the most important phytocannabinoids, namely, (-)-cannabidiol (-CBD), from inexpensive and readily available starting material

Supplementary Legends 1-4 and Materials from Activation of Apoptosis by 1-Hydroxy-5,7-Dimethoxy-2-Naphthalene-Carboxaldehyde, a Novel Compound from Aegle marmelos

Supplementary Figure 1 from Activation of Apoptosis by 1-Hydroxy-5,7-Dimethoxy-2-Naphthalene-Carboxaldehyde, a Novel Compound from Aegle marmelos

Supplementary Figure 2 from Activation of Apoptosis by 1-Hydroxy-5,7-Dimethoxy-2-Naphthalene-Carboxaldehyde, a Novel Compound from Aegle marmelos

Supplementary Figure 4 from Activation of Apoptosis by 1-Hydroxy-5,7-Dimethoxy-2-Naphthalene-Carboxaldehyde, a Novel Compound from Aegle marmelos

Supplementary Figure 3 from Activation of Apoptosis by 1-Hydroxy-5,7-Dimethoxy-2-Naphthalene-Carboxaldehyde, a Novel Compound from Aegle marmelos

Food ingredients hold a higher nutritional value as a botanical supplement playing a vital role in modifying and maintaining the physiological conditions that improve human health benefits. The Kashmir saffron (Crocus sativus L; KCS) obtained from dried stigmas is known for its aroma precursors and apocarotenoid derivatives, imparting a wide range of medicinal values and therapeutic benefits. In the present study, a simultaneous determination of apocarotenoids and flavonoids in stigma-based botanical supplements was carried out using analytical investigations. The high-performance thin-layer chromatography-based qualitative analysis of the raw material (stigmas, stamens, and tepals) and stigma extract has been carried out to identify apocarotenoids and flavonoids. The rapid HPLC-PDA method for the simultaneous quantification of KCS apocarotenoids was robust, precise ( 0.99), and accurate (80-110%) as per the single-laboratory validation data. Furthermore, the combined-expanded uncertainty (95%; K = 2) was calculated and found as 0.0035-0.007% (

Background Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19 pandemic, has infected more than 179 million people worldwide. Testing of infected individuals is crucial for identification and isolation, thereby preventing further spread of the disease. Presently, Taqman™ Reverse Transcription Real Time PCR is considered gold standard, and is the most common technique used for molecular testing of COVID-19, though it requires sophisticated equipments, expertise and is also relatively expensive. Objective Development and optimization of an alternate molecular testing method for the diagnosis of COVID-19, through a two step Reverse Transcription Loop-mediated isothermal AMPlification (RT-LAMP). Results Primers for LAMP were carefully designed for discrimination from other closely related human pathogenic coronaviruses. Care was also taken that primer binding sites are present in conserved regions of SARS-CoV2. Our analysis shows that the primer binding sites are well conserved in all the variants of concern (VOC) and variants of interest (VOI), notified by World Health Organization (WHO). These lineages include B.1.1.7, B.1.351, P.1, B.1.617.2, B.1.427/B.1.429, P.2, B.1.525, P.3, B.1.526 and B.1.617.1. Various DNA polymerases with strand displacement activity were evaluated and conditions were optimized for LAMP amplification and visualization. Different LAMP primer sets were also evaluated using synthetic templates as well as patient samples. Conclusion In a double blind study, the RT-LAMP assay was validated on more than 150 patient samples at two different sites. The RT-LAMP assay appeared to be 89.2% accurate when compared to the Taqman™ rt-RT-PCR assay.

Correction for ‘Chrysomycins A–C, antileukemic naphthocoumarins from Streptomyces sporoverrucosus’ by Shreyans K. Jain et al., RSC Adv., 2013, 3, 21046–21053, https://doi.org/10.1039/c3ra42884b.

Bacterial cell has always been an attractive target for anti-infective drug discovery. MurA (UDP-N-acetylglucosamine enolpyruvyl transferase) enzyme of Escherichia coli (E.coli) is crucial for peptidoglycan biosynthetic pathway, as it is involved in the early stages of bacterial cell wall biosynthesis. In the present study we aim to identify novel chemical structures targeting the MurA enzyme. For screening purpose, we used in silico approach (pharmacophore based strategy) for 52,026 library compounds (Chembridge, Chemdiv and in house synthetics) which resulted in identification of 50 compounds. These compounds were screened in vitro against MurA enzyme and release of inorganic phosphate (Pi) was estimated. Two compounds (IN00152 and IN00156) were found to inhibit MurA enzyme > 70% in primary screening and IC50 of 14.03 to 32.30 μM respectively. These two hits were further evaluated for their mode of inhibition studies and whole-cell activity where we observed 2-4 folds increase in activity in presence of Permeabilizer EDTA (Ethylenediaminetetraacetic acid). Combination studies were also performed with known antibiotics in presence of EDTA. Hits are reported for the first time against this target and our report also support the use of OM permeabilizer in combination with antibacterial compounds to address the permeability and efficacy issue. These lead hits can be further optimized for drug discovery. KEY POINTS: • Emerging Gram negative resistant strains is a matter of concern. • Need for new screening strategies to cope with drying up antibiotics pipeline. • Outer membrane permeabilizers could be useful to improve potency of molecules to reach its target.

An attempt is made to uncover the physical meaning and significance of the obscure Lanczos tensor field which is regarded as a potential of the Weyl field. Despite being a fundamental building block of any metric theory of gravity, the Lanczos tensor has not been paid proper attention as it deserves. By providing an elucidation on this tensor field through its derivation in some particularly chosen spacetimes, we try to find its adequate interpretation. Though the Lanczos field is traditionally introduced as a gravitational analogue of the electromagnetic 4-potential field, the performed study unearths its another feature - a relativistic analogue of the Newtonian gravitational force field. A new domain of applicability of the Lanczos tensor is introduced which corroborates this new feature of the tensor., Comment: 27 pages, no figures

Four lipopeptaibols, namely, lipovelutibols A-D, were recently isolated from psychrotrophic fungus Trichoderma velutinum and reported to have significant cytotoxic activity against HL-60, MDA-MD-231, A549, and LS180 cancer cell lines. In the present study, these peptides were synthesized in a solution using a segment condensation approach. The conformational analysis of these peptides carried out using CD spectrophotometry revealed the formation of 310-helix, and the NMR-VT experiments showed intramolecular hydrogen bonding for NH-5, NH-6, and NH-7. Lipovelutibol D showed potent cytotoxic activity and was chosen for lead optimization. It involved N- and C-terminal truncation, N- and C-terminal modification, random deletion, l/d configuration replacement, and other synthetic analogues. These were tested against various breast cancer cell lines. The C-terminal aldehyde analogue resulting from lead optimization of lipovelutibol D was found to have almost twofold enhanced cytotoxicity against MDA-MB-231 breast cancer cell lines.

Seven cytochalasins, 19,20-epoxycytochalasin N, cytochalasin P1, deacetyl 19,20-epoxycytochalasin C, 19,20-epoxycytochalasin D, 19,20-epoxycytochalasin C, cytochalasin D, and cytochalasin C, were isolated from a fungal (Rosellinia sanctae-cruciana) crude extract. A cytotoxicity assay (sulforhodamine B) was performed on a series of cancer cell lines: HT-29, A-549, PC-3, HCT-116, SW-620, and MCF-7. Simultaneously, the liquid chromatography–mass spectrometry (LC–MS)/MS profile of 19,20-epoxycytochalasin C-treated cell lines revealed that 19,20-epoxycytochalasin C (m/z 524.25) oxidized to a metabolite of m/z 522.25 Da (−2 Da (−2H) from 19,20-epoxycytochalasin C). Further chemical oxidation of 19,20-epoxycytochalasin C using the Dess–Martin reagent produced an identical metabolite. It has been noticed that the parent molecule (19,20-epoxycytochalasin C) showed an IC50 of 650 nM (on HT-29), whereas for the oxidized metabolite (m/z 522.24) of 19,20-epoxycytochalasin C, the IC50 was >10 μM. It is clear that the parent molecule had 16 times higher cytotoxic potential as compared to the oxidized metabolite. The spectroscopic investigation indicated that the oxidation of the hydroxyl (−OH) group occurred at the C7 position in 19,20-epoxycyctochalsin C and led to the inactivation of 19,20-epoxycytochalasin C. Further, cell cycle analysis and histopathological evidence support the findings, and CDK2 could be a possible target of 19,20-epoxycyctochalasin C.

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The Spike (S) protein of SARS-CoV-2 expressed on the viral cell surface is of particular importance as it facilitates viral entry into the host cells. The S protein is heavily glycosylated with 22 N-glycosylation sites and a few N-glycosylation sites. During the viral surface protein synthesis via the host ribosomal machinery, glycosylation is an essential step in post-translational modifications (PTMs) and consequently vital for its life cycle, structure, immune evasion, and cell infection. Interestingly, the S protein of SARS-CoV-2 and the host receptor protein, ACE2, are also extensively glycosylated and these surface glycans are critical for the viral-host cell interaction for viral entry. The glycosylation pathway of both virus (hijacked from the host biosynthetic machinery) and target cells crucially affect SARS-CoV-2 infection at different levels. For example, the glycosaminoglycans (GAGs) of host cells serve as a cofactor as they interact with the receptor-binding domain (RBD) of S-glycoprotein and play a protective role in host immune evasion via masking the viral peptide epitopes. Hence, the post-translational glycan biosynthesis, processing, and transport events could be potential targets for developing therapeutic drugs and vaccines. Especially, inhibition of the N-glycan biosynthesis pathway amplifies S protein proteolysis and, thus, blocks viral entry. The chemical inhibitors of SARS-CoV-2 glycosylation could be evaluated for Covid-19. In this review, we discuss the current status of the chemical inhibitors (both natural and synthetically designed inhibitors) of viral glycosylation for Covid-19 and provide a future perspective. It could be an important strategy in targeting the various emerging SARS-CoV-2 variants of concern (VOCs), as these inhibitors are postulated to aid in reducing the viral load as well as infectivity.

The study reports a protocol for the regeneration of Glycyrrhiza glabra plantlet from the leaf explant. Notably, the chemical analysis of various developmental stages revealed presence of glycyrrhizin in the underground (7.0–29.8 µg/g) & aerial (7.3–23.4 µg/g) tissues of the in vitro regenerated plants, which was otherwise not detected in the aerial tissues of the field plant. Glycyrrhizin accumulation was reduced or undetected in the regenerated plants transferred to the glasshouse and subsequently under field conditions. Further, spatio-temporal relative gene expression analysis of aerial tissues of in-vitro regenerated G. glabra showed expression of all the known genes committed to glycyrrhizin pathway. In the shoot system, maximum expression of squalene epoxidase (7.9 fold), β-amyrin synthase (21.8 folds), Licorice β-amyrin 11-oxidase (5.9 folds) and UDP-glucosyltransferase (1.7 folds) was observed in different months. However, no expression was detected in the aerial tissues of the field grown plant. Also, a correlation was found between the expression patterns of Licorice β-amyrin 11-oxidase with glycyrrhizin accumulation. This is the first study demonstrating the presence of glycyrrhizin in the aerial tissues of the in-vitro regenerated Glycyrrhiza plant. This study will help in understanding glycyrrhizin regulation, precursor accumulation and their transport. Also, it will unlock the possibilities of understanding and enhancing glycyrrhizin biosynthesis and accumulation in the plant, under in-vitro conditions.

First, total synthesis of the cell surface phospholipomannan anchor [β-Manp-(1 → 2)-β-Manp]n-(1 → 2)-β-Manp-(1 → 2)-α-Manp-1 → P-(O → 6)-α-Manp-(1 → 2)-Inositol-1-P-(O → 1)-phytoceramide of Candida...

Velutibol A (1), a new 14-residue peptaibol was isolated from the Himalayan cold habitat fungus Trichoderma velutinum. The structural characterization was carried out by 1D and 2D NMR studies, and tandem mass studies, and Marfey's method aided in determining the stereochemistry of the amino acids. The CD analysis revealed folding of the peptide in a 310-helical conformation. The intramolecular H-bonding was determined by an NMR-VT experiment. Cytotoxic evaluation was carried out against a panel of cancer cell lines. The cell cycle assay was carried out on human myeloid leukaemia (HL-60) cells and revealed the formation of apoptotic bodies and DNA damage in a dose-dependent manner. Three other peptaibols namely velutibol B (2), velutibol C (3), and velutibol D (4) were also isolated in trace amounts from the psychotropic fungus and characterized through tandem mass spectroscopy and Marfey's analysis.

A concise, protection-group free and sequential route has been developed for the synthesis of the nitroimidazole based FDA-approved multi-drug resistant anti-tuberculosis drug, Delamanid and anti-leishmanial lead candidate VL-2098. The synthesis required chiral epoxides (11 and 17) as key intermediates. The chiral epoxide 11 was synthesised by sequential reaction cascades viz., allylation, selective N-arylation, Mitsunobu etherification, Sharpless asymmetric dihydroxylation and epoxidation, which do not require any special/dry reaction conditions. The steps involved towards the synthesis of epoxide also worked nicely in gram scales. After the synthesis of epoxide 11, the synthesis of Delamanid was achieved by reaction with 2-bromo-4-nitroimidazole 12 with an overall yield of 27%. Similarly, anti-leishmanial lead candidate VL-2098 was also synthesized in an overall yield of 36%.

Dengue is a serious public health concern worldwide, with ∼3 billion people at risk of contracting dengue virus (DENV) infections, with some suffering severe consequences of disease and leading to death. Currently, there is no broad use vaccine or drug available for the prevention or treatment of dengue, which leaves only anti-mosquito strategies to combat the dengue menace. The present study is an extension of our earlier study aimed at determining the in vitro and in vivo protective effects of a plant-derived phytopharmaceutical drug for the treatment of dengue. In our previous report, we had identified a methanolic extract of aerial parts of Cissampelos pareira to exhibit in vitro and in vivo anti-dengue activity against all the four DENV serotypes. The dried aerial parts of C. pareira supplied by local vendors were often found to be mixed with aerial parts of another plant of the same Menispermaceae family, Cocculus hirsutus, which shares common homology with C. pareira. In the current study, we have found C. hirsutus to have more potent anti-dengue activity as compared with C. pareira. The stem part of C. hirsutus was found to be more potent (∼25 times) than the aerial part (stem and leaf) irrespective of the extraction solvent used, viz., denatured spirit, hydro-alcohol (50:50), and aqueous. Moreover, the anti-dengue activity of stem extract in all the solvents was comparable. Hence, an aqueous extract of the stem of C. hirsutus (AQCH) was selected due to greater regulatory compliance. Five chemical markers, viz., Sinococuline, 20-Hydroxyecdysone, Makisterone-A, Magnoflorine, and Coniferyl alcohol, were identified in fingerprinting analysis. In a test of primary dengue infection in the AG129 mice model, AQCH extract at 25 mg/kg body weight exhibited protection when administered four and three times a day. The AQCH was also protective in the secondary DENV-infected AG129 mice model at 25 mg/kg/dose when administered four and three times a day. Additionally, the AQCH extract reduced serum viremia and small intestinal pathologies, viz., viral load, pro-inflammatory cytokines, and vascular leakage. Based on these findings, we have undertaken the potential preclinical development of C. hirsutus-based phytopharmaceutical, which could be studied further for its clinical development for treating dengue.

The dark matter problem is one of the most pressing problems in modern physics. As there is no well-established claim from a direct detection experiment supporting the existence of the illusive dark matter that has been postulated to explain the flat rotation curves of galaxies, and since the whole issue of an alternative theory of gravity remains controversial, it may be worth to reconsider the familiar ground of general relativity (GR) itself for a possible way out. It has recently been discovered that a skew-symmetric rank-three tensor field - the Lanczos tensor field - that generates the Weyl tensor differentially, provides a proper relativistic analogue of the Newtonian gravitational force. By taking account of its conformal invariance, the Lanczos tensor leads to a modified acceleration law which can explain, within the framework of GR itself, the flat rotation curves of galaxies without the need for any dark matter whatsoever., Comment: Received an Honorable Mention in the 2021 Essay Competition of the Gravity Research Foundation

Phenyl hydrazine was the first hydrazine derivative prepared by Emil Fisher in 1875 for the characterization of sugars via hydrazones formation. Since then, various chemical applications have been ...

Background: Cyclin-dependent kinases play a central role in the control of cell division and therefore it is not surprising that cancer exhibits some features that disturb the normal controls over the cell cycle. Previous studies related to the development of 3-Pyrimidinylazaindole (Meriolin) derivatives as novel Cyclin dependent kinase inhibitors highlighted 4ab as the most potent inhibitor. Objective: The main objective of the current study was to understand the mode of cell death and the effect of 4ab on major cellular networking pathways in cancer. Method: Preliminary apoptotic studies were carried out using flowcytometer and electron microscope. The effect on cellular signalling was studied via western blotting. Results: 4ab was found to inhibit the enzymatic activity of CDK2. The inhibition of CDK2 activity was found to be associated with the down-regulation of P-cdc-25 and arrest of cells in G0-G1 phase of the cell cycle in lymphoblastic leukemia cells. Further, 4ab was found to affect AKT-mToR pathway by down-regulating the expression of major proteins including P-m-TOR (2448), P110α, P-AKT (S473) and P-p-70S6K. Conclusion: Current study shows that the potent anticancer potential of 4ab is mediated via cellular apoptosis, dysregulation of mitochondrial membrane potential and arrest of G1 phase in Molt-4 cells. Further, target-based studies showed the effect of 4ab on one of the major cellular signalling pathways deregulated in cancer.

BACKGROUND/AIMS Excessive exposure to UV radiation negatively affects the human skin, characterized by photo-damage (premature aging & carcinogenesis). UV-B radiation causes about 90% of non-melanoma skin cancers by damaging de-oxy ribonucleic acids (DNA). We have previously reported that UV-B radiation induces skin photodamage through oxidative & Endoplasmic Reticulum (ER) stresses and Glycyrrhizic acid (GA), a natural triterpene, protects skin cells against such stresses. UV-B radiation elicits signalling cascade by activation of proteins involved in sensing, signalling, and repair process of DNA damage. In this study, we explored the effects & mechanisms of Glycyrrhizic acid (GA) against UV-B -induced photodamage using a well established cellular model. METHODS We used primary human dermal fibroblasts as a cellular model. The cells were cultured in the presence or absence of GA for 3,6, & 24 h. Effect of UV-B was assessed by examining cell viability, cell morphology, oxidative stress, ER stress, DNA damage & cellular autophagy levels through biochemical assays, microscopy & protein expression studies. RESULTS In this study, we have determined the effect of GA on autophagy mediated DNA damage response system as the main mechanism in preventing photodamage due to UV-B -irradiation to primary human dermal fibroblasts (HDFs). GA treatment to UV-B exposed HDFs, significantly inhibited cell death, oxidative & ER stress responses, prevented Cyclobutane Pyrimidine dimer (CPD) DNA adduct formation, and DNA fragmentation via modulation of UV-B induced autophagic flux. Present results showed that GA treatment quenched reactive oxygen species (ROS), relieved ER stress response, improved autophagy (6 hr's post-UV-B -irradiation) and prevented UV-B induced DNA damage. CONCLUSION The present study links autophagy induction by GA as the main mechanism in the prevention of DNA damage and provides a mechanistic basis for the photoprotective effect of GA and suggests that GA can be potentially developed as a promising agent against UV-B induced skin photo-damage.

Santonin, a natural product, was aromatized with molecular iodine as the catalyst. The new compound was characterized as ( S)-methyl-2-(7-hydroxy-5,8-dimethylnaphthalen-2-yl) propanoate (2) based on 2D NMR spectroscopic data. Structurally, compound 2 was highly similar to the anti-inflammatory drug naproxen. The new naproxen analogue had significant potency against cyclooxygenase 1 and 2 (IC50 = 31.0 and 66.1 μM, respectively).

Background Exploration of microbes isolated from north western Himalayas for bioactive natural products. Results A strain of Trichoderma lixii (IIIM-B4) was isolated from Bacopa monnieri L. The ITS based rDNA gene sequence of strain IIIM-B4 displayed 99% sequence similarity with different Trichoderma harzianum species complex. The highest score was displayed for Hypocrea lixii strain FJ462763 followed by H. nigricans strain NBRC31285, Trichoderma lixii strain CBS 110080, T. afroharzianum strain CBS124620 and Trichoderma guizhouense BPI:GJS 08135 respectively. Position of T. lixii (IIIM-B4) in phylogenetic tree suggested separate identity of the strain. Microbial dynamics of T. lixii (IIIM-B4) was investigated for small peptides. Medium to long chain length peptaibols of 11 residue (Group A), 14 residue (Group B) and 17 residue (Group C) were identified using Matrix Assisted Laser Desorption/Ionization-Time of Flight (MALDI-TOF) mass spectrometer. Optimization is undeniably a desideratum for maximized production of desirable metabolites from microbial strain. Here optimization studies were carried out on T. lixii (IIIM-B4) using different growth media through Intact Cell Mass Spectrometry (ICMS). A multifold increase was obtained in production of 11 residue peptaibols using rose bengal medium. Out of these, one of them named as Tribacopin AV was isolated and sequenced through mass studied. It was found novel as having unique sequence Ac-Gly-Leu-Leu-Leu-Ala-Leu-Pro-Leu-Aib-Val-Gln-OH. It was found to have antifungal activity against Candida albicans (25 μg/mL MIC). Conclusion In this study, we isolated a strain of T. lixii (IIIM-B4) producing medium and long chain peptaibols. One of them named as Tribacopin AV was found novel as having unique sequence Ac-Gly-Leu-Leu-Leu-Ala-Leu-Pro-Leu-Aib-Val-Gln-OH, which had antifungal properties. Electronic supplementary material The online version of this article (10.1186/s12866-019-1477-8) contains supplementary material, which is available to authorized users.

Rohitukine (referred to as RHK) is a bioactive chromone alkaloid isolated from the leaves of plant Dysoxylum binectariferum, which has been reported to possess diverse pharmacological properties for the treatment of inflammatory bowel disease (IBD), diarrhoea and anti-lipidemic. However, the underlying mechanism by which RHK exerts its anti-inflammatory activity has not yet demonstrated. This study aimed to elucidate the anti-inflammatory mechanism of RHK using lipopolysaccharide (LPS) - stimulated J774A.1 macrophage cells and in-vivo inflammatory models. Results demonstrated that RHK treatment could significantly decrease the LPS-induced production of nitric oxide, prostaglandin E2 (PGE2), interleukins (ILs) and tumour necrosis factor (TNF)-α in J774A.1 cells. Molecular studies revealed that RHK inhibited the activation of upstream mediator nuclear factor-κB by suppressing the phosphorylation of IκBα and p65. In in-vivo experiments showed prominent anti-inflammatory activity of RHK. Thus, RHK could be considered as a promising candidate for the treatment of inflammatory diseases.

NLRP3 inflammasome is an important therapeutic target for a number of human diseases. Herein, computationally designed series of quinazolin-4(3 H)-ones were synthesized using iodine-catalyzed coupling of arylalkynes (or styrenes) with O-aminobenzamides. The key event in this transformation involves the oxidative cleavage of the C-C triple/double bond and the release of formaldehyde. The reaction relies on the C-N bond formation along with the C-C bond cleavage under metal-free conditions. The nitro-substituted quinazolin-4(3 H)-one 2k inhibited NLRP3 inflammasome (IC50 5 μM) via the suppression of IL-1β release from ATP-stimulated J774A.1 cells.