Evaluation of Cytotoxicity of the Methanolic Extract of Red Sea Marine Sponge Xestospongia Testudinaria and Its Related Compounds Against MCF-7 Human Breast Cancer Cells.

Background: Breast cancer is a leading cause of death and one of the most common fatal medical conditions in the world. Chemical compounds of various types have been identified in the Red Sea marine sponge , including sterol esters, sterols, indole alkaloids, and brominated polyunsaturated fatty acids. These compounds have demonstrated promising biological features, which in cludes anti-inflammatory, cancer preventive, and antioxidant capacities.

A Liquid Chromatography Tandem Mass Spectrometry Method for the Simultaneous Estimation of the Dopamine Receptor Antagonist LE300 and Its N-methyl Metabolite in Plasma: Application to a Pharmacokinetic Study.

LE300 is a novel dopamine receptor antagonist used to treat cocaine addiction. In the current study, a sensitive and fast liquid chromatography-tandem mass spectrometry (LC-MS/MS) has been established and validated for the simultaneous analysis of LE300 and its -methyl metabolite, MLE300, in rat plasma with an application in a pharmacokinetic study. The chromatographic elution of LE300, MLE300, and Ponatinib (IS, internal standard), was carried out on a 50 mm C analytical column (ID: 2.

Virtual screening and molecular dynamics simulation study of abyssomicins as potential inhibitors of COVID-19 virus main protease and spike protein.

The lack of any effective cure for the infectious COVID-19 disease has created a sense of urgency and motivated the search for effective antiviral drugs. Abyssomicins are actinomyces-derived spirotetronates polyketides antibiotics known for their promising antibacterial, antitumor, and antiviral activities. In this study, computational approaches were used to investigate the binding mechanism and the inhibitory ability of 38 abyssomicins against the main protease (M) and the spike protein receptor-binding domain (RBD) of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2).

Chemical constituents from and their antimicrobial activity.

A new sesquiterpene lactone, 3β,10α-dihydroxy-10β-(hydroxymethyl)-8α-(4-hydroxymethacrylate)-1α,5α,6β7α-guai-4(15), 11(13)-dien-6,12-olide (), along with twenty-one known compounds, were identified from the aerial parts of . The structures of the isolated compounds were elucidated on the basis of spectroscopic evidences and correlated with known compounds. Compounds (, , and ) were identified from for the first time.

Tamoxifen charge transfer complexes with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone and 7,7,8,8-tetracyanoquinodimethan: Synthesis, spectroscopic characterization and theoretical study.

To understand bioactive molecule-receptor interactions it is important to understand the molecular complexation and structural recognition properties of the materials in question. To this aim, the electron donating bioactive molecule tamoxifen (TAM) was combined with the electron accepting molecules 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) and 7,7,8,8-tetracyanoquinodimethane (TCNQ) to form TAM-DDQ and TAM-TCNQ charge transfer (CT) complexes. The properties of the complexes in solution and solid, their donor-acceptor interactions were investigated, and their stability was assessed in acetonitrile.

Isolation and Characterization of Two Chalcone Derivatives with Anti-Hepatitis B Virus Activity from the Endemic Socotraen (Dragon's Blood Tree).

Hepatitis B virus (HBV) infection is prevalent and continues to be a global health concern. In this study, we determined the anti-hepatitis B virus (HBV) potential of the Socotra-endemic medicinal plant and isolated and characterized the responsible constituents. A bioassay-guided fractionation using different chromatographic techniques of the methanolic extract of led to the isolation of two chalcone derivatives.

Insecticidal Activity and Free Radical Scavenging Properties of Isolated Phytoconstituents from the Saudi Plant (Hochst.).

Chromatographic purification of the alcoholic extract from the aerial parts of the Saudi plant (Hochst.), Benth., resulted in five isolated phenolic compounds.

Sterols and Triterpenes from Growing in Saudi Arabia and Their Cytotoxic Activity.

A new lupane caffeoyl ester, lup-20(29)-ene 3β-caffeate-30-al (), and a new oleanane-type triterpene, 3-hydroxyolean-13(18)-en-12-one (), were isolated from the aerial parts of (Forssk), along with ten known triterpenes, including seven lupane-type lupeol (), 30-nor-lup-3-ol-20-one (), ∆-lupenone (), lup-20(29)-en-3,30-diol (), lupeol caffeate (), 30-hydroxy lup-20(29)-ene 3-caffeate (), and betunaldehyde (); three oleanane-type compounds were also identified, comprising -amyrone (), -amyrin (), and 11-oxo--amyrin (); together with six sterols, comprising -sitosterol (), stigmasterol (), 7-hydroxy--sitosterol (), 7-hydroxy-stigmasterol (), 7-keto--sitosterol (), and 7-keto-stigmasterol (). Their structures were elucidated using a variety of spectroscopic techniques, including 1D (H, C, and DEPT-135 C) and 2D (H-H COSY, H-C HSQC, and H-C HMBC) nuclear magnetic resonance (NMR) and accurate mass spectroscopy. Subsequently, the different plant extracts and some of the isolated compounds (, and ) were investigated for their possible cytotoxic activity in comparison to cisplatin against a wide array of aggressive cancer cell lines, such as colorectal cancer (HCT-116), hepatocellular carcinoma (HepG-2), and prostate cancer (PC-3) cell lines.

Vacillantins A and B, New Anthrone -glycosides, and a New Dihydroisocoumarin Glucoside from and Its Antioxidant Activities.

A new dihydroisocoumarin glucoside, vacillanoside (), and two new anthrone -glycosides microdantin derivatives; vacillantin A () and B (), together with nine known compounds belonging to the anthraquinone, anthrone and isocoumarin groups were isolated from the leaves of . The structures were determined based on spectroscopic evidence including 1D and 2D nuclear magnetic resonance (NMR) spectroscopy and high resolution mass spectrometry (HRESIMS) data, along with comparisons to reported data. The leaves were used to extract compounds with different solvents.

Evaluation of cytotoxicity, cell cycle arrest and apoptosis induced by L essential oil in human hepatocellular carcinoma cell line.

L. () commonly known as , is an essential oil bearing plant extensively being used in traditional system of medicine. However, the reports on the components and biological responses of essential oil (AG-EO) from Saudi Arabia are scarce.

Alpha-Amylase and Alpha-Glucosidase Enzyme Inhibition and Antioxidant Potential of 3-Oxolupenal and Katononic Acid Isolated from .

is traditionally used in diabetes treatment in many Arabian countries; however, scientific evidence is lacking. Hence, the present study explored the antidiabetic and antioxidant activities of the plant extracts and their purified compounds. The methanolic crude extract of was partitioned using a two-solvent system.

Molluscicidal activity of cardiac glycosides isolated from Adenium obesum.

Background: Terrestrial mollusks are one of most important agricultural pests worldwide. Natural phytochemicals have an extended history as a source of pesticides. This study was planned to isolate molluscicidal active compounds from the stems of Adenium obesum.

Comparative evaluation of cytotoxic, antimicrobial and antioxidant activities of the crude extracts of three species grown in Saudi Arabia.

Natural products from medicinal plants represent major resource of novel therapeutic substances for combating serious diseases including cancers and microbial infections. The genus (Family: Labiatae) represents a large and widespread group of species with a diversity of traditional uses in treatment of various ailments. Therefore, this research study aimed to evaluate the cytotoxic, antimicrobial and antioxidant activities of three species growing in Saudi Arabia namely Hocst.

The Phytochemical and Biological Investigation of Root Native to the Kingdom of Saudi Arabia.

Extensive phytochemical analysis of different root fractions of Courb. (Euphorbiaceae) has resulted in the isolation and identification of 22 secondary metabolites. 6-hydroxy-8-methoxycoumarin-7--β-d-glycopyranoside () and 2-hydroxymethyl -methyltryptamine () were isolated and identified as new compounds along with the known diterpenoid (, , , and ), triterpenoid ( and ), flavonoid (, , , , and ), coumarinolignan (⁻), coumarin (), pyrimidine (), indole (, ), and tyramine-derived molecules (⁻).

Prenylated flavonoids from Commiphora opobalsamum stem bark.

A phytochemical study on the stem bark of Commiphora opobalsamum looking for cytotoxic compounds afforded eleven flavonoids, including six previously undescribed prenylated congeners, comophorin A-E, and comophoroside A. The structures of the isolated compounds were elucidated on the basis of spectroscopic evidences and correlated with known compounds. Isolated compounds were biologically evaluated using in vitro cytotoxicity MTT-based assay against two cancer cell lines; namely human hepato-cellular carcinoma (HepG-2) and human breast adenocarcinoma (MCF-7).

New Cytotoxic Seco-Type Triterpene and Labdane-Type Diterpenes from Nuxia oppositifolia.

Chromatographic purification of the -hexane and dichloromethane extracts of aerial parts, growing in Saudi Arabia, resulted in the isolation and characterization of three new labdane-type diterpene acids, 2β-acetoxy-labda-7-en-15-oic acid (), 2β-acetoxy-7-oxolabda-8-en-15-oic acid (), 2β-acetoxy-6-oxolabda-7-en-15-oic acid (), and one new seco-triterpene, 3,4-seco olean-12-en-3,30 dioic acid (), together with 10 known lupane, oleanane and ursane-type triterpenes, as well as the common phytosterols, β-sitosterol and stigmasterol (-). Their structures have been assigned on the basis of different spectroscopic techniques including 1D and 2D NMR. Moreover, 13 of the isolated compounds were tested on the human cancer cell lines HeLa (cervical), A549 (lung) and MDA (breast), and most of the compounds showed potent cytotoxic activities in vitro.

Cytotoxic Compounds from the Saudi Red Sea Sponge Xestospongia testudinaria.

Bioassay-guided fractionation of the organic extract of the Red Sea sponge Xestospongia testudinaria led to the isolation of 13 compounds including two new sterol esters, xestosterol palmitate (2) and xestosterol ester of l6'-bromo-(7'E,11'E,l5'E)-hexadeca-7',11',l5'-triene-5',13'-diynoic acid (4), together with eleven known compounds: xestosterol (1), xestosterol ester of 18'-bromooctadeca-7'E,9'E-diene-7',15'-diynoic acid (3), and the brominated acetylenic fatty acid derivatives, (5E,11E,15E,19E)-20-bromoeicosa-5,11,15,19-tetraene-9,17-diynoic acid (5), 18,18-dibromo-(9E)-octadeca-9,17-diene-5,7-diynoic acid (6), 18-bromooctadeca-(9E,17E)-diene-7,15-diynoic acid (7), 18-bromooctadeca-(9E,13E,17E)-triene-7,15-diynoic acid (8), l6-bromo (7E,11E,l5E)hexadeca-7,11,l5-triene-5,13-diynoic acid (9), 2-methylmaleimide-5-oxime (10), maleimide-5-oxime (11), tetillapyrone (12), and nortetillapyrone (13). The chemical structures of the isolated compounds were accomplished using one- and two-dimensional NMR, infrared and high-resolution electron impact mass spectroscopy (1D, 2D NMR, IR and HREIMS), and by comparison with the data of the known compounds. The total alcoholic and n-hexane extracts showed remarkable cytotoxic activity against human cervical cancer (HeLa), human hepatocellular carcinoma (HepG-2), and human medulloblastoma (Daoy) cancer cell lines.

Studies on the Red Sea Sponge Haliclona sp. for its Chemical and Cytotoxic Properties.

Background: A great number of novel compounds with rich chemical diversity and significant bioactivity have been reported from Red Sea sponges.

Objective: To isolate, identify, and evaluate the cytotoxic activity of the chemical constituents of a sponge belonging to genus Haliclona collected from the Eastern coast of the Red Sea.

Materials And Methods: The total ethanolic extract of the titled sponge was subjected to intensive chromatographic fractionation and purification guided by cytotoxic bioassay toward various cancer cell lines.

Noncyanogenic Cyanoglucoside Cyclooxygenase Inhibitors from Simmondsia chinensis.

Two new noncyanogenic cyanoglucoside dimers, simmonosides A and B (1 and 2), were identified from the aqueous extract of jojoba (Simmondsia chinensis) leaves. Compounds 1 and 2 are the first examples of noncyanogenic cyanoglucoside dimers containing a unique four-membered ring, representing novel dimerization patterns at α,β-unsaturated carbons of a nitrile group in 1 and γ,δ-unsaturated carbons in 2. Their structures were elucidated based on spectroscopic evidence and electronic circular dichroism (ECD) calculations.

Lipoxygenase inhibitors from the latex of Calotropis Procera.

A radical-scavenging, guided phytochemical study of the latex of Calotropis Procera afforded five lignans (1-5), including a new one (4). The structural determination was accomplished using 1D- and 2D-NMR, high-resolution electrospray ionization mass spectrometry (HRESIMS), and correlation with known compounds. Among the isolated compounds, acylated lignans (3-5) showed stronger antioxidant activity than non-acylated derivatives (1,2).

A novel β-lactam derivative, albactam from the flowers of Albizia lebbeck with platelets anti-aggregatory activity in vitro.

A novel β-lactam derivative, albactam, was isolated from the alcoholic extract of the flowers of Albizia lebbeck. It showed a significant anti-aggregatory activity against adenosine diphosphate and arachidonic acid induced guinea-pigs' platelets aggregation in vitro. Six more known compounds were also isolated and fully characterized by measuring 1D and 2D NMR, two of them are the triterpenes β-amyrin and 11α, 12α-oxidotaraxerol, two ceramide derivatives and two flavonoids, kampferol 3-O-rutinoside and rutin.

Revision of the absolute configuration at C(23) of lanostanoids and isolation of secondary metabolites from formosan soft coral Nephthea erecta.

Three new oxygenated ergostanoids, 1-3, one known ergostanoid, 4, one new trinoreudesmadienone, 5, one new calamenene type sesquiterpene, 6, and one known aristolane-type sesquiterpene, (-)-aristolone (7), have been isolated from the AcOEt extract of the soft coral Nephthea erecta. The structures of these compounds were determined by extensive spectroscopic and X-ray crystallographic analysis, as well as Mosher's method. We revised the absolute configuration at C(23) in the side chain of some lanostanoids as a result of the Mosher's products of 1 (i.

Cytotoxic lupane-, secolupane-, and oleanane-type triterpenes from Viburnum awabuki.

Bioassay-guided fractionation of the methanolic extract of Viburnum awabuki afforded two new lupane triterpene derivatives; 6 beta-hydroxyl-3,20-dioxo-30 norlupane-28-oic acid (1) and 3,4-secolup-4,20-dihydroxy-3,28-dioic acid-3-oic acid methyl ester (2), along with seven known lupane and oleanane-type triterpenes (3-9). The structure of the isolated compounds was assigned using different spectroscopic techniques including 1D and 2D NMR. The 13CNMR data of compounds 5 and 9 is reported for the first time.

Prenylbicyclogermacrane diterpenoids from the formosan soft coral Nephthea elongata.

Seven new prenylbicyclogermacrane diterpenoids, pacificins K--Q (1--7), were isolated from the methylene chloride solubles of the Formosan soft coral Nephthea elongata. Their structures were elucidated by extensive spectroscopic analysis and their cytotoxicity against selected cancer cells was measured in vitro.