Ingenines A and B, Two New Alkaloids from the Indonesian Sponge Acanthostrongylophora ingens

As a continuation of the work on EtOAc fraction of the Indonesian sponge Acanthostrongylophora ingens, 2 new alkaloids: one pyrimidine-β-carboline alkaloid named ingenine A (2) and one pyrimidine-γ-carboline alkaloid named ingenine B (3), along with annomontine (1) were isolated. Their structures were unambiguously established on the basis of NMR spectroscopy ((1) H, (13)C, (1) H-(1) H COSY, HMQC, and HMBC) and mass spectral data. This is the first report of isolation pyrimidine-γ-carboline alkaloid from natural source. Compounds 1 and 3 showed pronounced cytotoxicity against the murine lymphoma L5178Y cancer cell line with ED50 7.8 and 9.1 μg/mL respectively, while compound 2 showed weak activity.

Stigmasterol Tetracosanoate, a New Stigmasterol Ester from the Egyptian Blepharis ciliaris

A new stigmasterol ester: stigmasterol tetracosanoate (3), along with 7 compounds: β-sitosterol (1), stigmasterol (2), (2S,3S,4R)-2[(2'R)-2'-(hydroxyeicosanoyl amino) octadecane-1,3,4-triol (4), apigenin (5), β-sitosterol-3-O-β-D-glucopyranoside (6), stigmasterol-3-O-β-D-glucopyranose (7), and apigenin-7-O-β-D-glucopyranoside (8) were isolated from Blepharis ciliaris aerial parts. Compounds 1, 2, and 5-7 are reported here for the first time from the plant and 4 for the first time from the family. GCMS analysis revealed the presence of 45 fatty acids, 53 hydrocarbons, and 24 sterols. The different fractions exhibited mild cytotoxic in brine shrimp assay and anti-hyperglycaemic activities. The EtOAc fraction and TME (total MeOH extract) showed weak anti-malarial activity against P. falciparum. The CHCl3 fraction gave potent -anti-inflammatory activity compared with indomethacin.

Urgineaglyceride A: a new monoacylglycerol from the Egyptian Drimia maritima bulbs

One new compound, (2S)-1-O-(Z)-tetracos-6-enoate glycerol (1) named urgineaglyceride A, along with six known compounds, 3,5,7,3',5'-pentahydroxydihydroflavonol (2), stigmasterol (3), (25S)-5β-furostane-3β-22α-26-triol (4), scillaridin A (5), (2S)-(+)-2-hydroxynaringenin-4'-O-β-D-glucopyranoside (6) and quercetin-3'-O-β-D-glucopyranoside (7), were isolated from the EtOAc fraction of Drimia maritima (L.) Stearn bulbs. Their structures were secured based on their IR, UV, 1D and 2D NMR data, in addition to HR-MS data and comparison with the literature data. The isolated compounds were evaluated for their in vitro growth inhibitory activity against A549 non-small cell lung cancer (NSCLC), U373 glioblastoma (GBM) and PC-3 prostate cancer cell lines. Compounds 2 and 3 displayed variable activities against the tested cancer cell lines. Compound 2 was a selective inhibitor of the NSCLC cell line with an IC₅₀ of 2.3 μM, whereas 3 was selective against GBM with IC₅₀ of 0.5 μM and against PC-3 with 2.0 μM.

Didemnacerides A and B: two new glycerides from Red Sea ascidian Didemnum species

Two new glycerides, didemnacerides A (1) and B (2), together with three known sterols, 24-ethyl-25-hydroxycholesterol (3), cholest-6-en-3,5,8-triol (4) and cholestane-3β,5α,6β-26-tetrol (5), were isolated from the Red Sea ascidian Didemnum sp. Their structures were elucidated by using extensive 1D ((1)H, (13)C) and 2D ((1)H-(1)H COSY, HSQC and HMBC) NMR studies and mass spectroscopic data (GC-MS and HR-MS) as well as alkaline hydrolysis followed by GC-MS and NMR spectral analyses of the fatty acid methyl esters. This is the first report of compounds 3-5 from the Red Sea ascidian Didemnum species.

New Nitrogenous Compounds from Anisotes trisulcus

Re-investigation of the methanolic extract of Anisotes trisulcus (Forssk.) Nees aerial parts led to the isolation of two new tricyclic quinazoline alkaloids, 8-amino-7,8,9,11-tetrahydro-6H-pyrido[2,1-b]- quinazoline-2,6-diol (4) and 8-amino-3,6-dihydroxy-7,8,9-trihydro-6H-pyrido[2,1-b]quinazoline- 11-one (5), and two quaternary ammonium compounds, (dimethylamino)-N-(hydroxymethyl)-N,Ndimethyl methanaminium chloride (6) and N-[(carboxyamino)methyl]-N,N-dimethyl ethanaminium chloride (7), together with three known compounds, peganine (1), vasicinone (2), and anisotine (3). The structures of these compounds were established on the basis of physical, chemical, and spectral data (UV, IR, MS, 1D and 2D NMR), as well as by comparison with authentic samples. GC-MS analysis of the fatty acid methyl esters and unsaponifiable matter revealed the presence of 46 fatty acids, 53 hydrocarbons, and 18 sterols. The different extracts were evaluated for their antihyperglycaemic activities. The MeOH, n-hexane, and EtOAc extracts exhibited a significant hypoglycaemic effect

Non-Alkaloidal Compounds from the Bulbs of the Egyptian Plant Pancratium maritimum

Phytochemical investigation of the cytotoxic fractions of fresh bulbs of Pancratium maritimum L. led to the isolation and structure identification of two new compounds, pancricin (1) and pancrichromone (4), together with four known compounds, including 2,4-dihydroxy-6- methoxy-3-methyl acetophenone (2), 5-formylfurfuryl acetate (3), 7-β-D-glucosyloxy-5-hydroxy-2- methylchromone (5), and ethyl-b-D-glucopyranoside (6). Their structures were established on the basis of 1D and 2D NMR spectroscopy (1H, 13C, COSY, HSQC, and HMBC), as well as HR mass spectral analyses. The compounds were evaluated for their antimigratory and antiproliferative activities against the highly metastatic human prostate cancer cell line (PC-3M). Compound 5 was the most active compound displaying good activity in the proliferation assay comparable to that of the positive control 4-hydroxyphenylmethylene hydantoin, while it displayed only weak antimigratory activity compared to the positive control 4-ethylmercaptophenylmethylene hydantoin.

Theonellamide G, a potent antifungal and cytotoxic bicyclic glycopeptide from the Red Sea marine sponge Theonella swinhoei

In our search for bioactive metabolites from marine organisms, we have investigated the polar fraction of the organic extract of the Red Sea sponge Theonella swinhoei. Successive chromatographic separations and final HPLC purification of the potent antifungal fraction afforded a new bicyclic glycopeptide, theonellamide G (1). The structure of the peptide was determined using extensive 1D and 2D NMR and high-resolution mass spectral determinations. The absolute configuration of theonellamide G was determined by chemical degradation and 2D NMR spectroscopy. Theonellamide G showed potent antifungal activity towards wild and amphotericin B-resistant strains of Candida albicans with IC₅₀ of 4.49 and 2.0 μM, respectively. Additionally, it displayed cytotoxic activity against the human colon adenocarcinoma cell line (HCT-16) with IC₅₀ of 6.0 μM. These findings provide further insight into the chemical diversity and biological activities of this class of compounds.

Proceraside A, a new cardiac glycoside from the root barks of Calotropis procera with in vitro anticancer effects

We have studied the ethyl acetate fraction of the methanolic extract of the root barks of Calotropis procera (Asclepiadaceae) from Egypt. Bioassay-directed fractionation and final purification of the extract resulted in the identification of a new cardenolide glycoside named proceraside A (1) together with two known compounds, frugoside (2) and calotropin (3). Their structures were elucidated by extensive NMR studies and mass spectrometric data. The in vitro cytotoxicity of the isolated compounds was evaluated against A549 non-small cell lung cancer, U373 glioblastoma and PC-3 prostate cancer cell lines. They showed potent activity against the tested cancer cell lines with IC50 ranging from 0.005 to 0.3 μg/mL. Cisplatin was used as positive control.

New chromone and triglyceride from Cucumis melo seeds

Re-investigation of the MeOH extract of the seeds of Cucumis melo L. var. reticulatus (Cucurbitaceae) led to the isolation of a new chromone derivative (5,7- dihydroxy-2-[2-(3-methoxy-4-hydroxyphenyl)ethyl]chromone (5) and a triglyceride (1,3-di-(6Z,9Z)-docosa-6,9-dienoyl-2-(6Z) hexacos-6-enoylglycerol (1), together with three known compounds; alpha-spinasterol (2), stigmasta-7,22,25-trien-3-ol (3), and D:B-friedoolean-5-ene-3-beta-ol (4), are reported from this species for the first time. Their structures were determined by extensive 1D (1H, 13C, and DEPT) and 2D (1H-1H COSY, HMQC, and HMBC) NMR and mass spectral measurements. Compound 5 displayed significant cytotoxic activity against L5178Y cells, with an ED50 of 5 microM. The MeOH extract and 5 showed antioxidant activity using the DPPH assay.

New Chromone and Triglyceride from Cucumis melo Seeds

Re-investigation of the MeOH extract of the seeds of Cucumis melo L. var. reticulatus (Cucurbitaceae) led to the isolation of a new chromone derivative (5,7-dihydroxy-2-[2-(3-methoxy-4-hydroxyphenyl)ethyl]chromone (5) and a triglyceride (1,3-di-(6 Z,9 Z)-docosa-6,9-dienoyl-2-(6 Z) hexacos-6-enoylglycerol (1), together with three known compounds; α-spinasterol (2), stigmasta-7,22,25-trien-3-ol (3), and D:B-friedoolean-5-ene-3-β-ol (4), are reported from this species for the first time. Their structures were determined by extensive 1D (1H, 13C, and DEPT) and 2D (1H-1H COSY, HMQC, and HMBC) NMR and mass spectral measurements. Compound 5 displayed significant cytotoxic activity against L5178Y cells, with an ED50 of 5 μM. The MeOH extract and 5 showed antioxidant activity using the DPPH assay.

New alkaloids from Pancratium maritimum

As a part of ongoing search efforts for the discovery of anticancer lead entities from natural sources, bulbs and flowers of the amaryllidaceous plant Pancratium maritimum have been investigated. Fractionation of the extracts of the fresh flowers and bulbs of P. maritimum led to the isolation of four new alkaloids, namely pancrimatines A (1) and B (2), norismine (3), and pancrimatine C (4), together with the previously reported N-methyl-8,9-methylenedioxy-6-phenanthridone (5), trispheridine (6), and N-methyl-8,9-methylenedioxyphenanthridine (7). The structures of these alkaloids were established on the basis of extensive 1D and 2D NMR and high-resolution mass spectral analyses as well as comparison with the literature. Compounds 2 and 7 showed antiproliferative and antimigratory activity against the highly metastatic human prostate cancer cell line PC-3 cells without cytotoxicity. The phenanthridine alkaloid class was identified as having potential for use to control prostate cancer proliferation and migration.

New constituents from the rhizomes of Egyptian Iris germanica L

Chemical investigation of the methanolic extract of the rhizomes of Iris germanica L. (Iridaceae) afforded two new compounds; irigenin S (7) and iriside A (12), together with ten known compounds: stigmasterol (1), a-irone (2), γ-irone (3), 3-hydroxy-5-methoxyacetophenone (4), irilone (5), irisolidone (6), irigenin (8), stigmasterol-3-O-β-D-glucopyranoside (9), irilone 4'-O-β-D-glucopyranoside (10) and iridin (11). Their structures were established by UV, IR, 1D (¹H and ¹³C) and 2D (¹H-¹H COSY, HMQC, and HMBC) NMR spectroscopy, in addition to mass spectroscopic data and comparison with literature data. The methanolic extract was evaluated for its antimicrobial activity. Both the methanolic extract and the isolated flavonoids were tested for their anti-inflammatory activity.

Diacarperoxide S, New Norterpene Cyclic Peroxide from the Sponge Diacarnus Megaspinorhabdosa

Re-investigation of the methanolic extract of the sponge Diacarnus megaspinorhabdosa afforded one new norsesterpene cyclic peroxide diacarperoxide S (2), in addition to two known compounds sigmosceptrellin B (1) and nebularine (3). The structures of the isolated compounds were established on the basis of one and two dimensional NMR spectroscopic studies (1H, 13C, DEPT, COSY, HMQC, HMBC, and ROESY) as well as on mass spectral analysis. The isolated compounds were evaluated for their cytotoxic as well as antimicrobial activities.

Diacarperoxide S, new norterpene cyclic peroxide from the sponge Diacarnus megaspinorhabdosa

Re-investigation of the methanolic extract of the sponge Diacarnus megaspinorhabdosa afforded one new norsesterpene cyclic peroxide diacarperoxide S (2), in addition to two known compounds sigmosceptrellin B (1) and nebularine (3). The structures of the isolated compounds were established on the basis of one and two dimensional NMR spectroscopic studies (1H, 13C, DEPT, COSY, HMQC, HMBC, and ROESY) as well as on mass spectral analysis. The isolated compounds were evaluated for their cytotoxic as well as antimicrobial activities.

Callyaerins A-F and H, new cytotoxic cyclic peptides from the Indonesian marine sponge Callyspongia aerizusa

Bioassay guided fractionation of the EtOAc fraction of the sponge Callyspongia aerizusa yielded seven new cytotoxic cyclic peptides callyaerins A-F (1-6) and H (8). Their structures were determined using extensive 1D (1H, 13C and DEPT) and 2D (COSY, HMQC, HMBC, TOCSY, and ROESY) NMR and mass spectral (ESI and HRESI-TOF) data. All compounds were cyclic peptides containing ring systems of 5-9 amino acids and side chains of 2-5 amino acids in length. An unusual (Z)-2,3-diaminoacrylic acid unit provided the template for ring closure and afforded the linkage to the peptidic side chain which was always initiated with a proline moiety. All peptides contained three or more proline residues and the remaining residues were predominantly hydrophobic residues with all amino acids present in the l form. Callyaerins A-F (1-6) and H (8) showed biological activity in antibacterial assays and in various cytotoxicity assays employing different tumour cell-lines (L5178Y, HeLa, and PC12). Callyaerins E (5) and H (8) exhibited strong activity against the L5178Y cell line with ED50 values of 0.39 and 0.48 microM, respectively. On the other hand, callyaerin A (1) showed strong inhibitory properties towards C. albicans.

New 2-(2-Phenylethyl)chromone Derivatives from the Seeds of Cucumis melo L var. reticulatus

Chemical investigation of the methanolic extract of the seeds of Cucumis melo L. var. reticulatus (Cucurbitaceae) afforded three new chromone derivatives; 5,7-dihydroxy-2-[2-(4-hydroxyphenyl)ethyl]chromone 3, 5,7-dihydroxy-2-[2-(3,4-dihydroxyphenyl)ethyl]chromone 4, and 7-glucosyloxy-5-hydroxy-2-[2-(4-hydroxyphenyl)ethyl]chromone 6, together with three known compounds; β-amyrin 1, β-sitosterol 2, and β-sitosterol-3- O-β-glucopyranoside 5. Their structures were established by UV, IR, 1D and 2D NMR, in addition to mass spectroscopic data and comparison with literature data. The n-hexane and methanolic extracts were evaluated for their antimicrobial activity, as well as cytotoxic activity using the brine shrimp bioassay.

New 2-(2-phenylethyl)chromone derivatives from the seeds of Cucumis melo L var. reticulatus

Chemical investigation of the methanolic extract of the seeds of Cucumis melo L. var. reticulatus (Cucurbitaceae) afforded three new chromone derivatives; 5,7-dihydroxy-2-[2-(4-hydroxyphenyl)ethyl]chromone 3, 5,7-dihydroxy-2-[2-(3,4-dihydroxyphenyl)ethyl]chromone 4, and 7-glucosyloxy-5-hydroxy-2-[2-(4-hydroxyphenyl)ethyl]chromone 6, together with three known compounds; beta-amyrin 1, beta-sitosterol 2, and beta-sitosterol-3-O-beta-glucopyranoside 5. Their structures were established by UV, IR, 1D and 2D NMR, in addition to mass spectroscopic data and comparison with literature data. The n-hexane and methanolic extracts were evaluated for their antimicrobial activity, as well as cytotoxic activity using the brine shrimp bioassay.

Iotrochotamides I and II: new ceramides from the Indonesian sponge Iotrochota purpurea

Our search for biologically active marine natural products led to the isolation of two new ceramides, iotrochotamide I and iotrochotamide II, together with three known 6-bromoindole alkaloids (6-bromo-1H-indole-3-carbaldehyde, 6-bromo-1H-indole-3-carboxylic acid methyl ester, and 6-bromo-1H-indole-3-carboxylic acid ethyl ester) from the sponge Iotrochota purpurea collected in Indonesia. The structure elucidation of these compounds was secured by spectroscopic methods (1H, 13C, DEPT, COSY, HMQC and HMBC), accurate mass measurements (ESI, EI and GS-MS) as well as comparison with known compounds.

Portulene, a new diterpene from Portulaca oleracea L

Chromatographic fractionation of the chloroform extract of Portulaca oleracea L. growing in Egypt afforded a new clerodene diterpene portulene (1), in addition to the known compounds lupeol (2), beta-sitosterol (3), and daucosterol (4), which were reported for the first time from the title plant. The structures of the isolated compounds were unambiguously established through 1D, 2D, and mass spectral analyses. Co-treatment of CCl(4) hepatic injured rats with 70% alcohol extract of P. oleracea significantly restored the hepatic marker enzymes and total bilirubin to near-normal values, which demonstrated hepatoprotective activity. In addition, the P. oleracea extract showed antibacterial and antifungal activities.

Diacarperoxides, norterpene cyclic peroxides from the sponge Diacarnus megaspinorhabdosa

Chemical investigation of the hexane extract of the sponge Diacarnus megaspinorhabdosa provided a series of new norterpene derivatives including three norditerpene cyclic peroxides, diacarperoxides A, B, and C (1 to 3), four norsesterterpene cyclic peroxides, diacarperoxides D to G (4 to 7), and the acyclic norsesterterpene diacardiol A (8). In addition, known norterpene peroxide congeners were also isolated, which included a known norsesterterpene cyclic peroxide (9), nuapapuin A methyl ester (10), epimuqubilin B (11), methyl-2-epinuapapuinoate (12), and methyl diacarnoate A (13). The structures of the new compounds were established on the basis of one- and two-dimensional NMR spectroscopic studies ((1)H, (13)C, COSY, HMQC, HMBC, and ROESY) as well as by mass spectrometric analyses. The relative configuration of chiral centers at C-2, C-3, and C-6 was assigned by established empirical rules. All compounds were evaluated for their cytotoxic properties in vitro using several human as well as murine cancer cell lines.

Acanthomine A, a new Pyrimidine-β-Carboline Alkaloid from the Sponge Acanthostrongylophora Ingens

Chemical investigation of the ethyl acetate extract of the sponge Acanthostrongylophora ingens afford one new pyrimidine-β-carboline alkaloid named acanthomine A (2), together with two known compounds annomontine (1) and 1,2,3,4-tetrahydronorharman-1-one (3). Their structures were unambiguously established on the basis of NMR spectroscopy (1H, 13C, 1H-1H COSY, HMQC and HMBC) and mass spectrometry. The isolated compounds were tested for cytotoxic activity using brine shrimp bioassay and different cancer cell lines.

Strepsiamide A-C, New Ceramides from the Marine Sponge Strepsichordaia Lendenfeldi

Investigation of the lipophilic extract of the Indonesian sponge Strepsichordaia lendenfeldi afforded three new ceramides, given the names strepsiamides A–C (1–3). The compounds showed cytotoxic activities against L5187Y and Hela cell lines. All structures were unambiguously established by 1D and 2D NMR spectroscopic and mass (EI-, APCI- and GC-MS) spectrometric data.

Cytotoxic Sesquiterpene Lactones of Egyptian Tanacetum santolinoides

The chloroform soluble fraction of the methanolic extract of the aerial parts of Tanacetum santolinoides afforded six sesquiterpene lactones. Tanacetolide A (1) was isolated for the first time from a natural source, in addition to five known sesquiterpene lactones. The structures were established on the basis of extensive studies of their 1D and 2D (1H-1H COSY, HMQC, HMBC, HOHAHA and NOESY) NMR spectra and FAB mass spectral determinations. The compounds showed good cytotoxic activity when tested using the brine shrimp bioassay.