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The ostrich oil of Struthio camelus (Ratite) found uses in folk medicine as an anti-inflammatory in eczema and contact dermatitis. The anti-inflammatory effect of a γ-lactone (5-hexyl-3H-furan-2-one) isolated from ostrich oil and its formulated nano-emulsion in formalin-induced paw edema was investigated in this study. Ostrich oil was saponified using a standard procedure, the aqueous residue was fractionated, purified, and characterized as γ-lactone (5-hexyl-3H-furan-2-one) through the interpretation of IR, NMR, and MS analyses. The γ-lactone was formulated as nano-emulsion using methylcellulose (MC) for oral solubilized form. The γ-lactone methylcellulose nanoparticles (γ-lactone-MC-NPs) were characterized for their size, shape, and encapsulation efficiency with a uniform size of 300 nm and 59.9% drug content. The γ-lactone was applied topically, while the formulated nanoparticles (NPs) were administered orally to rats. A non-steroidal anti-inflammatory drug (diclofenac gel) was used as a reference drug for topical use and ibuprofen suspension for oral administration. Edema was measured using the plethysmograph method. Both γ-lactone and γ-lactone-MC-NPs showed reduction of formalin-induced paw edema in rats and proved to be better than the reference drugs, diclofenac gel and ibuprofen emulsion. Histological examination of the skin tissue revealed increased skin thickness with subepidermal edema and mixed inflammatory cellular infiltration, which were significantly reduced by the γ-lactone compared to the positive control (p-value = 0.00013). Diuretic and toxicity studies of oral γ-lactone-MC-NPs were performed. No diuretic activity was observed. However, lethargy, drowsiness, and refusal to feeding observed may limit its oral administration.

Zygophyllum coccineum, an edible halophytic plant, is part of the traditional medicine chest in the Mediterranean region for symptomatic relief of diabetes, hypertension, wound healing, burns, infections, and rheumatoid arthritis pain. The current study aimed to characterize Z. coccineum phytoconstituents, and the evaluations of the anti-microbial-biofilm, and anti-cancers bioactivities of the plant’s mother liquor, i.e., aqueous-ethanolic extract, and its subsequent fractions. The in silico receptors interaction feasibility of Z. coccineum major constituents with Staph GyraseB, and human topoisomerase-IIβ (h-TOP-IIβ) were conducted to confirm the plant’s anti-microbial and anti-cancer biological activities. Thirty-eight secondary metabolites of flavonoids, stilbene, phenolic acids, alkaloids, and coumarin classes identified by LC-ESI-TOF-MS spectrometric analysis, and tiliroside (kaempferol-3-O-(6′′′′-p-coumaroyl)-glucoside, 19.8%), zygophyloside-F (12.78%), zygophyloside-G (9.67%), and isorhamnetin-3-O-glucoside (4.75%) were identified as the major constituents. A superior biofilm obliteration activity established the minimum biofilm eradication concentration (MBEC) for the chloroform fraction at 3.9–15.63 µg/mL, as compared to the positive controls (15.63–31.25 µg/mL) against all the microbial strains that produced the biofilm under study, except the Aspergillus fumigatus. The aqueous-ethanolic extract showed cytotoxic effects with IC50 values at 3.47, 3.19, and 2.27 µg/mL against MCF-7, HCT-116, and HepG2 cell-lines, respectively, together with the inhibition of h-TOP-IIβ with IC50 value at 45.05 ng/mL in comparison to its standard referral inhibitor (staurosporine, IC50, 135.33 ng/mL). This conclusively established the anti-cancer activity of the aqueous-ethanolic extract that also validated by in silico receptor-binding predicted energy levels and receptor-site docking feasibility of the major constituents of the plant’s extract. The study helped to authenticate some of the traditional phytomedicinal properties of the anti-infectious nature of the plant.

Lead structure discovery mainly focuses on the identification of noncovalently binding ligands. Covalent linkage, however, is an essential binding mechanism for a multitude of successfully marketed drugs, although discovered by serendipity in most cases. We present a concept for the design of fragments covalently binding to proteases. Covalent linkage enables fragment binding unrelated to affinity to shallow protein binding sites and at the same time allows differentiated targeted hit verification and binding location verification through mass spectrometry. We describe a systematic and rational computational approach for the identification of covalently binding fragments from compound collections inhibiting enteroviral 3C protease, a target with high therapeutic potential. By implementing reactive groups potentially forming covalent bonds as a chemical feature in our 3D pharmacophore methodology, covalent binders were discovered by high-throughput virtual screening. We present careful experimental validation of the virtual hits using enzymatic assays and mass spectrometry unraveling a novel, previously unknown irreversible inhibition of the 3C protease by phenylthiomethyl ketone-based fragments. Subsequent synthetic optimization through fragment growing and reactivity analysis against catalytic and noncatalytic cysteines revealed specific irreversible 3C protease inhibition.

Zygophyllum coccineum, an edible halophytic plant, is part of the traditional medicine chest in the Mediterranean region for symptomatic relief of diabetes, hypertension, wound healing, burns, infections, and rheumatoid arthritis pain. The current study aimed to characterize Z. coccineum phytoconstituents, and the evaluations of the anti-microbial-biofilm, and anti-cancers bioactivities of the plant&rsquo, s mother liquor, i.e., aqueous-ethanolic extract, and its subsequent fractions. The in silico receptors interaction feasibility of Z. coccineum major constituents with Staph GyraseB, and human topoisomerase-II&beta, (h-TOP-II&beta, ) were conducted to confirm the plant&rsquo, s anti-microbial and anti-cancer biological activities. Thirty-eight secondary metabolites of flavonoids, stilbene, phenolic acids, alkaloids, and coumarin classes identified by LC-ESI-TOF-MS spectrometric analysis, and tiliroside (kaempferol-3-O-(6&prime, &prime, p-coumaroyl)-glucoside, 19.8%), zygophyloside-F (12.78%), zygophyloside-G (9.67%), and isorhamnetin-3-O-glucoside (4.75%) were identified as the major constituents. A superior biofilm obliteration activity established the minimum biofilm eradication concentration (MBEC) for the chloroform fraction at 3.9&ndash, 15.63 &micro, g/mL, as compared to the positive controls (15.63&ndash, 31.25 &micro, g/mL) against all the microbial strains that produced the biofilm under study, except the Aspergillus fumigatus. The aqueous-ethanolic extract showed cytotoxic effects with IC50 values at 3.47, 3.19, and 2.27 &micro, g/mL against MCF-7, HCT-116, and HepG2 cell-lines, respectively, together with the inhibition of h-TOP-II&beta, with IC50 value at 45.05 ng/mL in comparison to its standard referral inhibitor (staurosporine, IC50, 135.33 ng/mL). This conclusively established the anti-cancer activity of the aqueous-ethanolic extract that also validated by in silico receptor-binding predicted energy levels and receptor-site docking feasibility of the major constituents of the plant&rsquo, s extract. The study helped to authenticate some of the traditional phytomedicinal properties of the anti-infectious nature of the plant.

Griseofulvin 1 is an important antifungal agent that has recently received attention due to its antiproliferative activity in mammalian cancer cells. Study of SAR of some griseofulvin analogues has led to the identification of 2′-benzyloxy griseofulvin 3, a more potent analogue which retards tumor growth through inhibition of centrosomal clustering. However, similar to griseofulvin 1, compound 3 exhibited poor aqueous solubility. In order to improve the poor water solubility, six new griseofulvin analogues 5–10 were synthesized and tested for their antiproliferative activity and water solubility. The semicarbazone 9 and aminoguanidine 10 analogues were the most potent against HCT116 and MCF-7 cell lines. In combination studies, compound 9 was found to exert synergistic effects with tamoxifen and 5-fluorouracil against MCF-7 and HCT116 cells proliferation, respectively. The flow cytometric analysis of effect of 9 on cell cycle progression revealed G2/M arrest in HCT116. In addition, compound 9 induced apoptosis in MCF-7 cells. Finally, all synthesized analogues revealed higher water solubility than griseofulvin 1 and benzyloxy analogue 3 in pH 1.2 and 6.8 buffer solutions.

We report a ligand-free copper-catalyzed Goldberg coupling of a spirocyclic lactam with an aryl iodide or bromide to provide an N-aryl spirocyclic lactam in good to excellent yields. The protocol is applicable to a broad diversity of spirocyclic lactams. The corresponding products can be used for the preparation of tetra- and pent-cyclic compounds 4–7 as potential therapeutic agents in the treatment of diffuse large B-cell lymphoma (DLBCL) and triple negative breast cancer (TNBC).

The coupling of aryl iodides with lactams (I) tolerates various functional groups in both partners to give N-arylated products in good yields.

Anaerobic incubation of prednisone 1 with human intestinal bacteria (HIB) afforded nine metabolites: 5beta-androst-1-ene-3,11,17-trione 3, 3alpha-hydroxy-5alpha-androstane-11,17-dione 4, 3beta,17alpha,20-trihydroxy-5alpha-pregnan-11-one 5, 3alpha,17alpha-dihydroxy-5alpha-pregnane-11,20-dione 6, 3alpha,17alpha-dihydroxy-5beta-pregnane-11,20-dione 7, 3beta,17beta-dihydroxy-5alpha-androstan-11-one 8beta, 3beta,17alpha-dihydroxy-5alpha-androstan-11-one 8alpha, 3alpha,17beta-dihydroxy-5alpha-androstan-11-one 9beta, and 3alpha,17alpha-dihydroxy-5alpha-androstan-11-one 9alpha. The structures of these metabolites (3-9) were elucidated using several spectroscopic techniques. Computer-aided prediction of potential biological activities of the isolated prednisone metabolites (3-9) revealed potential inhibition of prostaglandin E2 9-ketoreductase (PGE2 9-KR). Docking studies applied to PGE2 9-KR allowed recommendation of the metabolites 4, 8beta, and 8alpha for further pharmacological study as PGE2 9-KR inhibitors.

As part of an ongoing effort to develop new antineoplastic agents, a series of substituted 3,4-dihydro- and 1,2,3,4-tetrahydro-benzo[4,5]imidazo[1,2-a]pyrimidine derivatives (5–19) were synthesized. 1,2,3,4-Tetrahydrobenzo[4,5]imidazo[1,2-a]pyrimidine-2-one derivatives (5–7) were prepared via one-pot two-component thermal cyclization reaction of 2-aminobenzimidazole 1 and P-substituted methyl cinnamates (2–4). Vilsmir-Haack formylation of these derivatives (5–7) afforded the 2-chloro-3-carboxaldehyde targets (8–10) followed by nucleophilic displacement of the chloro atom in the 3-carboxaldehyde compounds (8–10) to yield the remaining final targets (11–19). The structures of the synthesized derivatives (5–19) were confirmed by means of IR,1H NMR, MS and elemental analyses. The synthesized derivatives (5–19) were subjected to the National Cancer Institute (NCI)in vitro disease human cell screening panel assay. 2-Chloro-4-phenyl-3,4-dihydrobenzo[4,5]imidazo[1,2-a]pyrimidine-3-carboxyaldehyde (8, NCI 722731) and 4-(4-methoxyphenyl)-2-(4-methylpiperazin-1 -yl)-3,4-dihydrobenzo[4,5]imidazo [1,2-a]pyrimidine-3-carboxaldehyde (18, NCI 722739) showed a variable degree of antineoplastic activity against some of the cell lines tested. 2-Chloro-4-(4-nitrophenyl)-3,4-dihy-drobenzo[4,5]imidazo[1,2-a]pyrimidine-3-carboxyaldehyde (10, NCI 722743) exhibited goodin vitro antineoplastic activity with subpanel disease selectivity against all the cell lines tested with log10 GI50 (M), the concentration that inhibits 50% of cell growth, values ranging from -5.08 to

A series of N-substituted-1,3-isoindolinedione derivatives (2-16) were synthesized for the purpose of defining the effect of N-substitution on the anticonvulsant activity of these derivatives. The target compounds (2-16) were obtained by condensation of phthalic anhydride with the corresponding amine derivative. The structures of the synthesized derivatives (2-16) were confirmed by means of IR, 1H-NMR, 13C-NMR, MS and elemental analyses. The anticonvulsant activity of all compounds (2-16) were evaluated by subcutaneous pentylenetetrazole seizure threshold test at doses of 0.2, 0.4 and 0.8 mmol/kg compared with sodium valproate as a positive control. Their neurotoxicity were determined by the rotorod test. Many of the present series of compounds showed good anticonvulsant activity at the tested doses, as compared to sodium valproate. Three of them (4, 6 and 11) exhibited 100% protection against convulsions, neurotoxicity and death at all tested doses. Out of the series, two compounds (12 and 13) were completely inactive with 100% mortality. 3-(p-chlorophenyl)-4-(1,3-dioxo-2,3-dihydro-1H-2-isoindolyl)butanoic acid derivative (11) has emerged as the most active compound which is 20 times more active than valproate with ED50 8.7, 169 mg/kg; TD50 413, 406 mg/kg and PI 47.5, 2.4. The results revealed the importance of the combination of baclofenic and phthalimide moieties (compound 11) as a promising anticonvulsant candidate.

After anaerobic incubation of arctiin (1) from the seeds of Arctium lappa with a human fecal suspension, six metabolites were formed, and their structures were identified as (-)-arctigenin (2), (2R,3R)-2-(3',4'-dihydroxybenzyl)-3-(3",4"-dimethoxybenzyl)butyrolactone (3), (2R,3R)-2-(3'-hydroxybenzyl)-3-(3",4"-dimethoxybenzyl)butyrolactone (4), (2R,3R)-2-(3'-hydroxybenzyl)-3-(3"-hydroxy-4"-methoxybenzyl)butyrolactone (5), (2R,3R)-2-(3'-hydroxybenzyl)-3-(3",4"-dihydroxybenzyl)butyrolactone (6), and (-)-enterolactone (7) by various spectroscopic means including two dimensional (2D)-NMR, mass spectrometry, and circular dichroism. A possible metabolic pathway was proposed on the basis of their structures and the time course of the transformation. Enterolactones obtained from the biotransformation of arctiin and secoisolariciresinol diglucoside (SDG, from the seeds of Linum usitatissium) by human intestinal bacteria were proved to be enantiomers, with the (-)-(2R,3R) and (+)-(2S,3S) configurations, respectively. Compound 6 showed the most potent proliferative effect on the growth of MCF-7 human breast cancer cells in culture among 1 and six metabolites, while it showed inhibitory activity on estradiol-mediated proliferation of MCF-7 cells at a concentration of 10 microM. These results indicate that the transformation of 1 by intestinal flora might be essential for the manifestation of the estrogenic and antiestrogenic activity of 1.

A series of novel medium-sized 13H-dibenzo[d,h][1,3,7]oxadiazecine-8,14-dione macrolides (18-27, 30, 32) were synthesized in an ongoing effort to develop new antineoplastic agents. The synthon 2-(2-aminobenzoylamino)-benzoic acid (7), for preparation of the target compounds, was prepared via the reaction of isatoic anhydride 5 and anthranilic acid 6. Nine compounds (18-20, 24-27, 30, 32) were subjected to National Cancer Institute (NCI) in vitro disease-oriented human cells screening panel assay. Among the compounds tested, 6-benzyl-13H-dibenzo[d,h][1,3,7]oxadiazecine-8,14-dione (26, NSC 721327), bearing the benzyl group at position 6, showed cytotoxic activity and subpanel selectivity against leukemia (CCRF-CEM), colon (HCC-2998), CNS (SNB-75) and melanoma (UACC-257) panels at log(10) GI(50) (M), compound concentration that inhibits 50% of cell growth, ranging from -4.08 to -4.59.

Forty-eight derivatives of phorbol (9) and isophorbol (14) were evaluated for their inhibition of human immunodeficiency virus (HIV)-1 induced cytopathic effects (CPE) on MT-4 cells, as well as their activation of protein kinase C (PKC), as indices of anti-HIV-1 and tumor promoting activities, respectively. Of these compounds, the most potent inhibition of CPE was observed in 12-O-tetradecanoylphorbol 13-acetate (8) and 12-O-acetylphorbol 13-decanoate (6). The former also showed the strongest PKC activation activity, while the latter showed no activity at 10 ng/ml. Both activities were generally observed in those phorbol derivatives with an A/B trans configuration, but not in the isophorbol derivatives with an A/B cis configuration. Acetylation of 20-OH in the phorbol derivatives significantly reduced the inhibition of CPE, as shown in 12-O-, 20-O-diacetylphorbol 13-decanoate (6a) (IC100=15.6 microg/ml) vs. compound 6 (IC100=0.0076 microg/ml), and 12-O-tetradecanoylphorbol 13,20-diacetate (8a) (IC100=15.6 microg/ml) vs. 12-O-tetradecanoylphorbol 13-acetate (8) (IC100=0.00048 microg/ml), except in the case of 12-O-decanoylphorbol 13-(2-methylbutyrate) (4) and phorbol 12,13-diacetate (9c). The reduction of a carbonyl group at C-3 abruptly reduced the inhibition of CPE, as observed in 3beta-hydroxyphorbol 12,13,20-triacetate (9f) (IC100=500 microg/ml) vs. phorbol 12,13,20-triacetate (9d) (IC100=62.5 microg/ml). Although 8 was equipotent in the inhibition of CPE, and activation of PKC, both activities were abruptly decreased by the acetylation of 20-OH and methylation of 4-OH [as in 8a and 4-O-methyl-12-O-tetradecanoylphorbol 13,20-diacetate (8b), respectively]. On the other hand, its positional isomer (12-O-acetylphorbol 13-tetradecanoate (8c) showed neither activities. The removal of a long acyl group in 8 led to a substantial loss of both activities, as shown in phorbol 13-acetate (9b). Of the 12-O-acetyl-13-O-acylphorbol derivatives, the highest inhibition of CPE was observed in 6, which has a dodecanoyl residue at C-13. Both an increase and decrease in the number of fatty acid carbon chains resulted in significant reduction of the inhibition of CPE.

Paeoniflorin (1) and its derivatives having in common a cage-like pinane skeleton with hemiketal-acetal system, were evaluated for their effects on memory impairment induced by scopolamine in mice using a step-down type passive avoidance task. In the test session, 1 and its derivatives were intraperitoneally (i.p.) administered at doses of 0.002, 0.01, 0.02 and 0.2 mmol/kg, and 30 min later (15 min before the experiment), scopolamine (1 mg/kg, i.p.) was given. These compounds showed dose-dependent attenuation in a dose range of 0.002-0.02 mmol/kg and also enhancement of scopolamine-induced decrease in step-down latency. The effects of these compounds, except that of 2',3',4',5'-O-tetraacetyl-3-O-methylpaeoniflorin (8), followed a bell-shaped dose response profile. 8-Debenzoyl-6-deglucosyl-3-O-methylpaeoniflorin (6) showed no significant increase in the step-down latency at all tested doses. Maximum step-down latency was obtained by 3-O-methylpaeoniflorin (3) and 2',3,3',4',5'-penta-O-methylpaeoniflorin (7) (the minimal effective dose was 0.002 mmol/kg). Relative to 3, debenzoylation, as in 8-debenzoyl-3-O-methylpaeoniflorin (4), slightly increased the latency, while deglucosylation, as in 6-deglucosyl-3-O-methylpaeoniflorin (5), significantly reduced the prolongation of latency. Removal of both glucose and benzoyl moieties resulted in the loss of activity as seen in 6. These results revealed that, in addition to the cage-like pinane skeleton, the benzoyl and the glucosyl moieties are important structural elements of the paeoniflorin skeleton as its effects on scopolamine-induced amnesia.

A series of 3(5)-substituted 1,2,4-triazole-5(3)-carboxylic acid amides, hydroxamic, hydrazide, iminosemicarbazide, semicarbazide and thiosemicarbazide have been synthesized. Most of the prepared compounds were tested for their growth inhibitory activity against Staph. aureus and E. coli and none of them revealed antibacterial activity at concentration up to 2.5 mg/mL. The 5(3)-iminosemicarbazides (8h, 9h, 10h, 11h), 5(3)-semicarbazides (8i, 9i, 10i, 11i) and 5(3)-thiosemicarbazides (8j, 9j, 10j) were chosen for evaluation of their potentialities to lower blood glucose level in rats. The oral glucose tolerance test was used as preliminary test for evaluation of hypoglycemic activity of these compounds. The tested compounds showed different onset and duration of action.

Spiro and sulfonamide derivatives have been found to be biologically active. In view of this importance, we report the synthesis of some new spiroheterocyclic naphthenes IV - VI.

3,5-Dibenzylidene-1-isopropy1-4-piperidinone (1) reacts with cyanothioacetamide to give 1,6-naphthyridine-2(1H) thione derivative 2. Reaction of 2 with halo ketones or halo esters followed by ring closure gives thieno[2,3-b][1,6]naphthyridine derivatives 5a—i, which are used as versatile intermediates in the synthesis of related heterocyclic ring systems as pyrimidothienonaphthyridines 10, 11, 14, and 15, oxazinothienonaphthyridine (13) and triazinothienonaphthyridine (9).

3,5-Dibenzylidene-1-isopropy1-4-piperidinone (1) reacts with cyanothioacetamide to give 1,6-naphthyridine-2(1H) thione derivative 2. Reaction of 2 with halo ketones or halo esters followed by ring closure gives thieno[2,3-b][1,6]naphthyridine derivatives 5a—i, which are used as versatile intermediates in the synthesis of related heterocyclic ring systems as pyrimidothienonaphthyridines 10, 11, 14, and 15, oxazinothienonaphthyridine (13) and triazinothienonaphthyridine (9).

Spiro and sulfonamide derivatives have been found to be biologically active. In view of this importance, we report the synthesis of some new spiroheterocyclic naphthenes IV - VI .

Seventeen thiopaeonimetabolin-I adducts were obtained as mixtures of diastereoisomers after incubation of paeoniflorin with Lactobacillus brevis in the presence of various thiols. Four compounds, 8-(n-hexylthio)- (8), 8-cyclopentylthio-, 8-(p-tolyl)thio- and 8-benzoylthio- (18) paeonimetabolins, showed 100% protection against pentylenetetrazole-induced convulsions at doses of 0.125, 0.25, or 0.50 mmol/kg, relative to valproic acid (100% protection at 1.5 mmol/kg). For 8 and 18, the principle anticonvulsant activity resided in the (7S)-isomers while (7R)-isomers showed muscle relaxation effects.

During the course of preparing anticonvulsant paeonimetabolin-I adducts, new paeonilactone-A adducts: 9-phenylthiopaeonilactone-A, 9-(o-tolylthio)paeonilactone-A, 9-(m-tolylthio)paeonilactone-A, 9-(p-tolylthio)-paeonilactone-A and 9-(2-naphthylthio)paeonilactone-A, were obtained along with expected paeonimetabolin-I adducts by anaerobic incubation of paeoniflorin from peony roots with Lactobacillus brevis in the presence of the aromatic thiols, phenylthiol, o-tolylthiol, m-tolylthiol, p-tolylthiol and 2-naphthylthiol. The structures of these compounds were determined by spectroscopic methods including two dimensional (2D) NMR.

Forty-eight derivatives of phorbol (9) and isophorbol (14) were evaluated for their inhibition of human immunodeficiency virus (HIV)-1 induced cytopathic effects (CPE) on MT-4 cells, as well as their activation of protein kinase C (PKC), as indices of anti-HIV-1 and tumor promoting activities, respectively. Of these compounds, the most potent inhibition of CPE was observed in 12-O-tetradecanoylphorbol 13-acetate (8) and 12-O-acetylphorbol 13-decanoate (6). The former also showed the strongest PKC activation activity, while the latter showed no activity at 10 ng/ml. Both activities were generally observed in those phorbol derivatives with an A/B trans configuration, but not in the isophorbol derivatives with an A/B cis configuration. Acetylation of 20-OH in the phorbol derivatives significantly reduced the inhibition of CPE, as shown in 12-O-, 20-O-diacetylphorbol 13-decanoate (6a) (IC100=15.6 μg/ml) vs. compound 6 (IC100=0.0076 μg/ml), and 12-O-tetradecanoylphorbol 13,20-diacetate (8a) (IC100=15.6 μg/ml) vs. 12-O-tetradecanoylphorbol 13-acetate (8) (IC100=0.00048 μg/ml), except in the case of 12-O-decanoylphorbol 13-(2-methylbutyrate) (4) and phorbol 12,13-diacetate (9c). The reduction of a carbonyl group at C-3 abruptly reduced the inhibition of CPE, as observed in 3β-hydroxyphorbol 12,13,20-triacetate (9f) (IC100=500 μg/ml) vs. phorbol 12,13,20-triacetate (9d) (IC100=62.5 μg/ml). Although 8 was equipotent in the inhibition of CPE, and activation of PKC, both activities were abruptly decreased by the acetylation of 20-OH and methylation of 4-OH [as in 8a and 4-O-methyl-12-O-tetradecanoylphorbol 13,20-diacetate (8b), respectively]. On the other hand, its positional isomer (12-O-acetylphorbol 13-tetradecanoate (8c) showed neither activities. The removal of a long acyl group in 8 led to a substantial loss of both activities, as shown in phorbol 13-acetate (9b). Of the 12-O-acetyl-13-O-acylphorbol derivatives, the highest inhibition of CPE was observed in 6, which has a dodecanoyl residue at C-13. Both an increase and decrease in the number of fatty acid carbon chains resulted in significant reduction of the inhibition of CPE.

A series of novel medium-sized 13H-dibenzo[d,h][1,3,7]oxadiazecine-8,14-dione macrolides (18–27, 30, 32) were synthesized in an ongoing effort to develop new antineoplastic agents. The synthon 2-(2-aminobenzoylamino)-benzoic acid (7), for preparation of the target compounds, was prepared via the reaction of isatoic anhydride 5 and anthranilic acid 6. Nine compounds (18–20, 24–27, 30, 32) were subjected to National Cancer Institute (NCI) in vitro disease-oriented human cells screening panel assay. Among the compounds tested, 6-benzyl-13H-dibenzo[d,h][1,3,7]oxadiazecine-8,14-dione (26, NSC 721327), bearing the benzyl group at position 6, showed cytotoxic activity and subpanel selectivity against leukemia (CCRF-CEM), colon (HCC-2998), CNS (SNB-75) and melanoma (UACC-257) panels at log10 GI50 (M), compound concentration that inhibits 50% of cell growth, ranging from −4.08 to −4.59.

The discovery of the inducible isoform of cyclooxygenase enzyme (COX-2) spurred the search for anti-inflammatory agents devoid of the undesirable effects associated with classical NSAIDs. New chlorzoxazone ester prodrugs (6-8) of some acidic NSAIDs (1-3) were designed, synthesized and evaluated as mutual prodrugs with the aim of improving the therapeutic potency and retard the adverse effects of gastrointestinal origin. The structure of the synthesized mutual ester prodrugs (6-8) were confirmed by IR, (1)H NMR, mass spectroscopy (MS) and their purity was ascertained by TLC and elemental analyses. In vitro chemical stability revealed that the synthesized ester prodrugs (6-8) are chemically stable in hydrochloric acid buffer pH 1.2 as a non-enzymatic simulated gastric fluid (SGF) and in phosphate buffer pH 7.4 as non-enzymatic simulated intestinal fluid (SIF). In 80% human plasma, the mutual prodrugs were found to be susceptible to enzymatic hydrolysis at relatively faster rate (t(1/2) approximately 37 and 34 min for prodrugs 6 and 7, respectively). Mutual ester prodrugs (6-8) were evaluated for their anti-inflammatory and muscle relaxation activities. Scanning electromicrographs of the stomach showed that the ester prodrugs induced very little irritancy in the gastric mucosa of rats after oral administration for 4days. In addition, docking of the mutual ester prodrugs (6-8) into COX-2 active site was conducted in order to predict the affinity and orientation of these prodrugs at the enzyme active site.

In trials to preserve the pharmacological profile and improve the bioavailability via lipophilicity increment of baclofen 1 and searching for more potent and less toxic muscle relaxants and analgesics, nine substituted cyclic analogues of 1 were designed and synthesized. The target derivatives 5-(4-chlorophenyl)-5,6-dihydro-1,3-oxazepin-7(4H)-one (11-19) were obtained through amide formation to the corresponding intermediates (2-10) followed by cyclization using acetic anhydride. The structures of the target compounds (11-19) were confirmed by IR, (1)H NMR, MS, and elemental analyses. The neuropharmacological activities of these lipophilic cyclic analogues (11-19) were assessed for their effects on motor activity, muscle relaxation, pain relief and impaired cognition, by intraperitoneal administration at a dose of 3mg/kg with reference to those of baclofen 1. Our results showed that compounds 11-14 are devoid of all of the tested pharmacological effects associated with 1. In all paradigms tested, undecyl, tridecyl, heptdec-8-enyl and benzyl substituted analogue derivatives (15, 16, 18, and 19) revealed a significant neurological activity being vividly favorable comparable with baclofen 1. 2-Benzyl-5-(4-chlorophenyl)-5,6-dihydro-1,3-oxazepin-7(4H)-one derivative 19 is the most active candidate with high significant neurological potencies, while 5-(4-chlorophenyl)-2-(dec-8-enyl)-5,6-dihydro-1,3-oxazepin-7(4H)-one derivative 17 displayed activity at relatively higher time interval. These results probe a new structurally distinct class incorporating 1,3-oxazepine nucleus as promising candidates as GABA(B) agonists for further investigations.

A new series of 1,3,4-thiadiazole-2-thione derivatives have been prepared and assayed for the inhibition of three physiologically relevant carbonic anhydrase (CA, EC 4.2.1.1) isozymes, the cytosolic human isozymes I and II, and the transmembrane, tumor-associated hCA IX. Against hCA I the investigated thiones, showed inhibition constants in the range of 2.55-222 microM, against hCA II in the range of 2.0-433 microM, and against hCA IX in the range of 1.25-148 microM. Compound 5c, 4-(4,5-dihydro-5-thioxo-1,3,4-thiadiazol-2-yl)-1-(5-nitro-2-oxoindolin-3-ylidene)semicarbazide showed interesting inhibition of the tumor-associated hCA IX with K(I) value of 1.25 microM, being the first non-sulfonamide type inhibitor of such activity. This result is rather important taking into consideration the known antitumor activity of thiones. In addition, docking of the tested compounds into CA II active site was performed in order to predict the affinity and orientation of these compounds at the isozyme active site. The results showed similar orientation of the target compounds at CA II active site compared with reported sulfonamide type CAIs with the thione group acting as a zinc-binding moiety.

Anaerobic incubation of phorbol (1) from Croton tiglium with human intestinal bacteria afforded five metabolites: isophorbol (2), deoxyphorbol (3), 4beta,9alpha,20-trihydroxy-13,15-seco-1,6,15-tigliatriene-3,13-dione (4), 4beta,9alpha,20-trihydroxy-15,16,17-trinor-1,6-tigliadiene-3,13-dione (5) and 4beta,9a,20-trihydroxy-14(13-->12)-abeo-12alphaH-1,6-tigliadiene-3,13-dione (6). All these metabolites (2-6) were identified and characterized by spectroscopic means, including two-dimensional (2D)-NMR. Nine defined strains from the human intestine showed an ability to transform 1 to these metabolites.

During the course of preparing anticonvulsant paeonimetabolin-I adducts, new paeonilactone-A adducts: 9-phenylthiopaeonilactone-A, 9-(o-tolylthio)paeonilactone-A, 9-(m-tolylthio)paeonilactone-A, 9-(p-tolylthio)-paeonilactone-A and 9-(2-naphthylthio)paeonilactone-A, were obtained along with expected paeonimetabolin-I adducts by anaerobic incubation of paeoniflorin from peony roots with Lactobacillus brevis in the presence of the aromatic thiols, phenylthiol, o-tolylthiol, m-tolylthiol, p-tolylthiol and 2-naphthylthiol. The structures of these compounds were determined by spectroscopic methods including two dimensional (2D) NMR.

Seventeen thiopaeonimetabolin-1 adducts were obtained as mixtures of diastereoisomers after incubation of paeoniflorin with Lactobacillus brevis in the presence of various thiols. The anticonvulsant activity of the adducts was investigated in mice using the maximal subcutaneous pentylenetetrazol seizure test and sodium valproate (1.5 mmol/kg) as a positive control. Thirteen adducts showed dose-dependent prolongation of latencies of clonic and tonic convulsions. Maximal protection against convulsions was effectively demonstrated by 8-(n-hexylthio)paeonimetabolin I (8) and 8-benzoylthiopaeonimetabolin I (18) at doses of 0.125 and 0.25 mmol/kg, respectively, while 100% protection was only achieved at 0.5 mmol/kg of 8-cyclopentylthiopaeonimetabolin I and 8-(p-tolylthio)paeonimetabolin I. The principal anticonvulsant activity of the diastereoisomers of 8 and 18 was attributed to their 7S-isomers [ED 50 values of 0.09 and 0.12 mmol/kg, and protective indices of 5.0 and 4.0 for 8 (75) and 18 (75), respectively], while the 7R counterparts [8 (7R) and 18 (7R)] showed a muscle relaxation effect.

Many studies indicated that polysorbate (PS) 80-coated polybutylcyanoacrylate (PBCA) nanoparticles can deliver drugs that poorly penetrate BBB to the brain. Also, the polyethylene glycolated-polybutylcyanoacrylate (PEG-PBCA) nanoparticles have a good safety profiles and sustained drug release. The purpose of this study is to compare between the ability of both PS80-coated PBCA nanoparticles and PEG-PBCA nanoparticles in targeting of tacrine to the brain. Rats treated with tacrine intravenously in three forms: 1) simple solution; 2) loaded on PS80-coated PBCA nanoparticles; 3) loaded on PEG-PBCA nanoparticles. Tacrine antiamnesic effect was tested using the passive avoidance reflex (PAR) test. Also tacrine concentrations in brain and liver were measured using HPLC. Results demonstrated that, both PS-80 coated and PEG-PBCA nanoparticles successfully enhanced brain delivery of tacrine in rats while PEG-PBCA nanoparticles have higher brain targeting ability and less liability to be up taken by the liver, this provides it more safety and longer duration.

Seventeen thiopaeonimetabolin-I adducts were obtained as mixtures of diastereoisomers after incubation of paeoniflorin with Lactobacillus brevis in the presence of various thiols. Four compounds, 8-(n-hexylthio)- (8), 8-cyclopentylthio-, 8-(p-tolyl)thio- and 8-benzoylthio- (18) paeonimetabolins, showed 100% protection against pentylenetetrazole-induced convulsions at doses of 0.125, 0.25, or 0.50 mmol/kg, relative to valproic acid (100% protection at 1.5 mmol/kg). For 8 and 18, the principle anticonvulsant activity resided in the (7S)-isomers while (7R)-isomers showed muscle relaxation effects.

In a one pot procedure, 18 compounds of 7-(substituted phenyl)-2-substituted-6,7-dihydro-4H-[1,2,4]triazolo[1,5-a] pyrimidin-5-one derivatives (16-33) have been synthesized. 3(5)-Amino-5(3)-substituted-1,2,4-triazole derivatives (7-12) were used as synthomes which were cyclo-condensed by fusion with substituted methyl cinnamate esters (13-15) to afford the target compounds (16-33). In an effort to develop new non-nucleoside antiviral agents, compounds 16-33 were evaluated for their anti-HIV-1 and anti-HSV-1 activities. Complete inhibition of the proliferation of HIV-1 viruses was achieved by compounds 22, 23 and 24 at concentrations of 25, 25 and 50 micrograms/ml, respectively. 7-Phenyl-2-(n-pentyl)-6,7-dihydro-4H-[1,2,4]triazolo[1,5-a]pyrimidin-5-one (19) exhibited potential activity against HSV-1 with 88% reduction in the viral plaques. The suggested marked specificity of this class of compounds as anti-HIV-1 and HSV-1 agents is discussed.