Imam Bakhsh Baloch

Bio-active compounds from Euphorbia cornigera Boiss.

Euphorbia cornigera Boiss. (Euphorbiaceae) roots extracted in various organic solvents were tested against Biomphalaria glabrata snails as molluscicide using Bayluscide as a control. Among these, acetone extract was found to be the most active (LC(50)=17.5 microg L(-1)) as compared to Bayluscide. The application of HPLC fractionation yielded ten (1-10) N-(2-aminobenzoyl)anthraniloy esters. Structure and the relative configuration of all the compounds were established through spectroscopic (UV, IR (1)H, (13)C NMR, 2-D NMR, HSQC, HMQC, HMBC, COSY-45 degrees , TOCSY, HOHAHA, HOESY, ROESY, NOESY, SECSY, NOE and mass measurements) techniques. On these basis the esters are named as: 3-O-[N-(2-aminobenzoyl)]-5-O-acetyl-20-O-angelylingenol (1), 3-O-[N-(2-aminobenzoyl)]anthraniloyl-5-O-angelyl-20-O-acetylingenol (2), 3-O-acetyl-5-O-[N-(2-aminobenzoyl)]anthraniloyl-20-O-angelylingenol (3), 3-O-acetyl-5-O-angelyl-20-O-[N-(2-aminobenzoyl)]anthraniloylingenol (4), 3-O-angelyl-5-O-acetyl-20-O-[N-(2-aminobenzoyl)]-anthraniloylingenol (5), 3-O-angelyl-5-O-[N-(2-aminobenzoyl)]anthraniloyl-20-O-acetylingenol (6), 3,20-O-diacetyl-5-O-[N-(2-aminobenzoyl)]anthraniloylingenol (7), 5,20-O-diacetyl-3-O-[N-(2-aminobenzoyl)]anthraniloylingenol (8), 3-O-[N-(2-aminobenzoyl)]anthraniloyl-20-O-acetylingenol (9) and 20-O-[N-(2-aminobenzoyl)]anthraniloyl-3-O-acetylingenol (10). The literature reveals that compounds 1-8 are new from plant kingdom, whereas 9 and 10 are known but not reported from this source earlier. Their molluscicidal activity (in terms of LC(50)) showed that all the compounds were 1.3-2.2 times more toxic than Bayluscide except 5 and 6.

In vitro anti-leishmanial and anti-fungal effects of new SbIII carboxylates

Ring opening of phthalic anhydride has been carried out in acetic acid with glycine, β-alanine, L-phenylalanine, and 4-aminobenzoic acid to yield, respectively, 2-{[(carboxymethyl)amino]carbonyl}benzoic acid (I), 2-{[(2-carboxyethyl)amino]carbonyl}benzoic acid (II), 2-{[(1-carboxy-2-phenylethyl)amino]carbonyl}benzoic acid (III), and 2-[(4-carboxyanilino)carbonyl]benzoic acid (IV). Compounds I-IV have been employed as ligands for Sb(III) center (complexes V-VIII) in aqueous medium. FTIR and 1H NMR spectra proved the deprotonation of carboxylic protons and coordination of imine group and thereby tridentate behaviour of the ligands as chelates. Elemental, MS, and TGA analytic data confirmed the structural hypothesis based on spectroscopic results. All the compounds have been assayed in vitro for anti-leishmanial and anti-fungal activities against five leishmanial strains L. major (JISH118), L. major (MHOM/PK/88/DESTO), L. tropica (K27), L. infantum (LEM3437), L. mex mex (LV4), and L. donovani (H43); and Aspergillus Flavus, Aspergillus Fumigants, Aspergillus Niger, and Fusarium Solani. Compound VII exhibited good anti-leishmanial as well as anti-fungal impacts comparable to reference drugs.

Irritant and co-carcinogenic diterpene esters from the latex of Euphorbia cauducifolia L.

Ten (1–10) irritant and mild co-carcinogenic diterpene esters were isolated from the latex of Euphorbia cauducifolia L. using bioassay-guided countercurrent distribution and other chromatographic techniques. The isolated compounds were characterized on the basis of spectroscopic results and mass measurements. As an outcome, the ingenane-type esters were established with the following structures: 3-O-angeloyl-17-O-palmatoylingenol (1), 3-O-palmatoyl-5-O-angeloylingenol (2), 5-O-angeloyl-17-O-palmatoylingenol (3), 3-O-angeloyl-5-O-palmatoylingenol (4), 17-O-(2Z,4E,6Z)-2,4,6-tetradecatrienoyl-20-O-palmatoylingenol (5), 5-O-angeloyl-17-O-benzoylingenol (6), 5-O-angeloyl-17,20-diacetoxyingenol (7), 3-O-angeloyl-17-O-benzoyl-20-acetoxyingenol (8), 3-acetoxy-5-O-angeloyl-17-O-benzoylingenol (9), and 5-O-angeloyl-3,17,20-triacetoxyingenol (10). Their biological screening revealed that they are moderate irritants, and low to moderate tumor promoters compared to TPA, but hardly showed any solitary carcinogenic activity. The isolated esters represent new compounds and were not reported before from any source.

Isolation and characterisation of new bio-active compounds from Euphorbia cornigera: cytotoxic ingenol esters

The aerial parts of Euphorbia cornigera Boiss., on extraction with MeOH, yielded new bio-active constituents (1, 2) and known compounds (3 and 4) after MTT cytotoxicity assay-guided fractionation and chromatographic separation were conducted. From the aerial parts of E. cornigera Boiss., new bio-active constituents were extracted in methanol. The extract was partitioned in different organic solvents and the ethylacetate-soluble portion was subjected to Craigs distribution. The MTT cytotoxicity assay-guided chromatographic separation yielded four (1–4), out of which two (1, 2) were new and two known (3, 4) bio-active compounds, and they are reported for the first time from this source. Their structure and relative stereochemistry were established by analysing spectroscopic and mass measurement data. The isolates were named as: 13-O-[(2Z,4E,6Z)]-deca-2,4,6-trienoylingenol (1), 13-O-( 2Z,4E,6Z)-deca-2,4,6-trienoyl-20-O-angeloylingenol (2), 13-O-dodecanoyl-20-O-hexanoylingenol (3) and 3-O-(2,3-dimethylbutanoyl)-13-O-dodecanoyl-20-O-hexadecanoylingenol (4). Literature revealed that compounds 1 and 2 are new metabolites, while 3 and 4 are known, and are reported for the first time from this source. Cytotoxicities of isolates were evaluated in terms of IC50 against RAW and HT-29 cell lines through MTT assay using ambrucin hydrochloride as a control. Compound 3 showed more activity than control, while 1, 2 and 4 were moderate.

Isolation and characterization of cytotoxic compounds from Euphorbia cornigera Boiss.

Methanolic extract of Euphorbia cornigera shoots was separated using HPLC, affording compounds 1–4. Their structures and relative stereochemistry were established after obtaining their spectroscopic (IR, 1H, 13C NMR COSY-45°, HOHAHA, HSQC, HMBC, NOESY, and mass measurement) data. On the basis of these data, the compounds were characterized as 3-O-(2,3-dimethylbutanoyl)-13-O-dodecanoyl-20-O-tetradecanoylingenol (1), 3-O-decanoyl-20-O-hexanoylingenol (2), 3-O-(2,3-dimethylbutanoyl)-13-O-dodecanoyl-20-O-hexadecanoylingenol (3), and 13-O-dodecanoyl-20-O-hexanoylingenol (4); among these compounds, two (1 and 2) were new metabolites while the rest (3 and 4) were known. The MTT cytotoxicity assay was carried out using amrubicin hydrochloride as a positive control. Compound 1 displayed IC50 as 5.0 and 2.9 μM against RAW and HT-29 cell lines, respectively, which is 5- and 1.5-folds stronger than the control with IC50 values of 25 and 4.36 μM, respectively.

An efficient method for the preparation of benzyl γ-ketohexanoates

Twenty acid chlorides, 4-(mono/di-benzyloxy)-4-ketobutanoyl chlorides (Ia–XXa) were synthesised by the reaction of monoesters of succinic acid with thionyl chloride. The product thus obtained (4-benzyloxy-4-ketobutanoyl chlorides) was treated with diethylcadmium to convert it into the corresponding keto-esters (Ib–XXb), the mono/di-benzyl-γ-ketohexanoates, with a good yield. All the compounds thus prepared were characterised by physical, spectroscopic (UV-VIS, IR, 1H NMR, 13C NMR), and mass measurements techniques.

New Bioactive Oleanane Type Compounds from Coriandrum sativum Linn.

Five (1–5) new bioactive oleanane type triterpenoids have been isolated from ethyl acetate soluble fraction of ethanolic extract of Coriandrum sativum Linn. of Umbelliferae family. Ethanolic extract of the whole plant was fractionated in organic solvents. Ethyl acetate fraction was subjected to column chromatography on HPLC RP-18 to get 1-oxo-11β,21β-dihydroxy-oleanane (1), 1-oxo-11β-hydroxy-21β-O-acetyloleanane (2), 1-oxo-11β-hydroxy-21β-O-angeloyloleanane (3), 1-oxo-11β-O-angeloyl-21β-O-acetyloleanane (4), and 1-oxo-11β,21β-O-dibenzoyloleanane (5). The structures were elucidated after analysis of spectroscopic data, UV, IR, NMR (1H, 13C, 1D, and 2D), and mass measurements. Suspension in water of crude ethyl acetate extract was employed to treat sheep with ringworm disease. All isolated compounds (1–5) displayed excellent activity in terms of inhibition zones, MICs, MBCs, and MFCs against both bacteria and fungi. Ethyl acetate extract showed excellent antiringworm activity in sheep.