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BackgroundSynthetic steroids, such as 9α-bromobeclomethasonedipropionate, have shown gastroprotective activity. For example, the potent glucocorticoid steroid, beclomethasone dipropionate, has been used for treatment of bowel ulcerations. The purpose of the present study was to evaluate the effect of a synthetic steroid, (20S)-22-acetoxymethyl-6β-methoxy-3α,5-dihydro-3′H-cyclopropa[3α,5]-5α-pregnane (AMDCP), on ethanol-induced gastric mucosa injuries in rats.Methodology/Principal FindingRats were divided into 8 groups. The negative control and ethanol control groups were administered Tween 20 (10%v/v) orally. The reference control group, 20 mg/kg omeprazole (10% Tween 20, 5 mL/kg), was administrated orally. The experimental groups received 1, 5, 10, 15 or 20 mg/kg of the AMDCP compound (10% Tween 20, 5 mL/kg). After 60 min, Tween 20 and absolute ethanol was given orally (5 mL/kg) to the negative control group and to the rest of the groups, and the rats were sacrificed an hour later. The acidity of gastric content, gastric wall mucus and areas of mucosal lesions were assessed. In addition, histology and immunohistochemistry of the gastric wall were assessed. Prostaglandin E2 (PGE2) and malondialdehyde (MDA) content were also measured. The ethanol control group exhibited severe mucosal lesion compared with the experimental groups with fewer mucosal lesions along with a reduction of edema and leukocyte infiltration. Immunohistochemical staining of Hsp70 and Bax proteins showed over-expression and under-expression, respectively, in the experimental groups. The experimental groups also exhibited high levels of PGE2 as well as a reduced amount of MDA. AMDCP decreased the acidity and lipid peroxidation and increased the levels of antioxidant enzymes.Conclusion/SignificanceThe current investigation evaluated the gastroprotective effects of AMDCP on ethanol-induced gastric mucosal lesions in rats. This study also suggests that AMDCP might be useful as a gastroprotective agent.

BackgroundMitrella kentii (M. kentii) (Bl.) Miq, is a tree-climbing liana that belongs to the family Annonaceae. The plant is rich with isoquinoline alkaloids, terpenylated dihydrochalcones and benzoic acids and has been reported to possess anti-inflammatory activity. The purpose of this study is to assess the gastroprotective effects of desmosdumotin C (DES), a new isolated bioactive compound from M. kentii, on gastric ulcer models in rats.MethodsDES was isolated from the bark of M. kentii. Experimental rats were orally pretreated with 5, 10 and 20 mg/kg of the isolated compound and were subsequently subjected to absolute ethanol-induced acute gastric ulcer. Gross evaluation, mucus content, gastric acidity and histological gastric lesions were assessed in vivo. The effects of DES on the anti-oxidant system, non-protein sulfhydryl (NP-SH) content, nitric oxide (NO)level, cyclooxygenase-2 (COX-2) enzyme activity, bcl-2-associated X (Bax) protein expression and Helicabacter pylori (H pylori) were also investigated.ResultsDES pre-treatment at the administered doses significantly attenuated ethanol-induced gastric ulcer; this was observed by decreased gastric ulcer area, reduced or absence of edema and leucocytes infiltration compared to the ulcer control group. It was found that DES maintained glutathione (GSH) level, decreased malondialdehyde (MDA) level, increased NP-SH content and NO level and inhibited COX-2 activity. The compound up regulated heat shock protein-70 (HSP-70) and down regulated Bax protein expression in the ulcerated tissue. DES showed interesting anti-H pylori effects. The efficacy of DES was accomplished safely without any signs of toxicity.ConclusionsThe current study reveals that DES demonstrated gastroprotective effects which could be attributed to its antioxidant effect, activation of HSP-70 protein, intervention with COX-2 inflammatory pathway and potent anti H pylori effect.

Three new limonoids, chisomicines A-C (1-3), have been isolated from the bark of Chisocheton ceramicus. Their structures were determined by 2D NMR, CD spectroscopic methods, and X-ray analysis. Chisomicine A (1) exhibited NO production inhibitory activity in J774.1 cells stimulated by LPS dose-dependently at high cell viability.

Background The design of new polymers able to filter the electromagnetic spectrum and absorb distinctly in the UV and high-energy part of visible spectrum is crucial for the development of semi-transparent solar cells. Herein, we report on the synthesis and spectroscopic, electrochemical, and photophysical characteristics of three new polymers, namely (i) Poly(triamterene-co-terephthalate), (ii) Poly[triamterene-co- 3-(2-pyridyl)-5,6-diphenyl-1,2,4-triazine-p,p′-disulfonamide], and (iii) Poly(5-hydroxyindole-2-carboxylate) that might show promise as materials for semi-transparent solar cells. Results The energy band gap, refractive index, dielectric constant, and optical conductivity of the electron donor polymer, poly(triamterene-co-terephthalate), were determined to be 2.92 eV, 1.56, 2.44 and 2.43 × 104 S cm−1, respectively. The synthesized electron acceptor polymers showed a relatively high refractive index, dielectric constant, and optical conductivity. The presence of a direct allowed transition was confirmed between intermolecular energy bands of the polymers. Conclusions The polymers showed relatively high energy gap and deep HOMO levels, making them strong absorbers of photons in the UV region and high energy part of the visible region. The synthesized donor and acceptors performed well relative to P3HT and fullerenes due to the close match of the HOMO and LUMO levels. With further development, the polymers could be viable for use as the active layers of semi-transparent solar cells.

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Cyclic 2-(N,N-dimethylaminomethyl)ferroceneboronate (DMAM-FcB) esters of a variety of 1,2-diols have been examined by gas and liquid chromatography as well as by mass spectrometry. Some comparisons have been made with analogous ferroceneboronate (FcB) esters. Under the conditions used for reversed-phase high-performance liquid chromatography, more of the FcB than of the DMAM-FcB esters were stable. Many of the derivatives were suitable for gas chromatography; the retention index increments for the dimethylaminomethyl substituent were on the order of 200 units on a methylsilicone phase. A satisfactory separation of diastereomeric boronates derived from chiral diols could be performed in the same achiral stationary phase. In most instances, the mass spectra of DMAM-FcB esters showed clear molecular ions along with prominent ions of m/z (M-44), resulting from a loss of the (CH3)2N radical. Evidence for the formation of mono-and bis-boronates of ecdysterone was obtained by fast atom bombardment mass spectrometry. KeywordsCyclic boronate, 2-(N,N-dimethylaminomethyl)ferroceneboronate, chromatography, gas chromatography-mass spectrometryBoronic acids have proved to be extremely versatile and effective reagents for the selective gas-phase analysis of 1,2-diols and of related compounds possessing suitably proximal functional groups. Many quantitative determinations have been based on the gas chromatography (GC) of boronate derivatives; the mildness and simplicity of the reactions involved are particularly advantageous with sensitive analytes.Comparable applications of liquid chromatography have been limited by the susceptibility of cyclic boronates to solvolysis; however, there are many instances in which such derivatives show considerable stability. Examples are cyclic boronates of di-t-glycols and of the di-s-threo-22,23-dihydroxylic group present in the brassinosteroids. Several boronic acids, including the recently developed naphthaleneboronic acids, phenanthreneboronic acid2, 1-cyanoisoindole-2-m-phenylboronic acid3, and dansylaminophenylboronic acid4, have been successfully applied to the determination of brassinosteroids by highperformance liquid chromatography (HPLC). More recently, ferroceneboronic acid has also been found to be suitable for this purpose.5 Cyclic ferroceneboronates had previously been introduced as very effective derivatives for the characterization and analysis of 1,2-and

The R-(+)-enantiomeric form of Dianin's compound and the S-(+)-enantiomeric form of its direct thiachroman analogue both obtained chromatographically employing a cellulose tris(3,5-dimethylphenylcarbamate) column, are shown to undergo supramolecular assembly to form a polar clathrate lattice which is stable even in the absence of a consolidating guest component.Crystal engineering is a major theme of current chemical research 1 . In particular the design of clathrates, in a classical sense cage-type multimolecular crystalline inclusion compounds, has not only inherent scientific interest but is also important for the supramolecular assembly of new systems with applications in, for example, drug delivery, isomer separation, optical resolutions, storage of toxic and reactive materials and second harmonic generation. It has now been firmly established that judicious modification of an appropriate host molecule, based on a knowledge of the crystal structure of the parent host lattice, can lead to new inclusion compounds 2 of both the channel 3 and true closed-cage clathrate 4,5 types. Scheme 1 Dianin's compound and structural variantsThe present work is concerned with crystal engineering related to Dianin's compound 1a, (Scheme 1), the remarkable inclusion properties of which were first reported in 1914 by A.P.Dianin 6 , a student and biographer of the chemist and composer Alexander Borodin. The parent host 1a, which does not possess an enforced intramolecular cavity, is particularly attractive from the viewpoint of carefully chosen structural modification. It offers multiple points of substitution, variation of the two functional groups and of crucial importance to the present work is chiral and can be resolved into its two enantiomers 7 . At the end of the 1960's it was established that both compound 1a 8 and its thia analogue 4-p-hydroxyphenyl-2,2,4-trimethylthiachroman, (ThiaDianin's compound), 2 9,10 , (Scheme 1), form isomorphous and isostructural clathrates in the centrosymmetric space group R 3 , with the two host lattices being stable even in the absence of a guest. Further packing modes involving 1a, demonstrating the breakdown of the isomorphous and isostructural behaviour of Dianin's compound along with computational stability studies on the host lattice have also been studied 11 . In a recent paper Jacobs et al. presented a quasiracemic organic host prepared from the cocrystallisation of the resolved enantiomers of Dianin's compound 1a and its mercapto analogue 1b 13 . Cocrystallisation of (R)-1a and (S)-1b from CCl 4 produced a CCl 4 clathrate structure in the polar and chiral space group R3 featuring an [SH … OH] 3 hexamer replacing the [OH] 6 and [SH] 6 hexamers of racemic 1a and 1b respectively. The reduction in symmetry from R 3 to R3 allowed for the polar ordering of the CCl 4 guest molecules, (two per cage), such that a preferential alignment of the C-Cl bonds along the polar axis toward the host phenolic moiety was achieved in the ratio of 85 : 15. Desolvation of this material however resulted ...