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Lichen species typically have a characteristic profile of secondary metabolites. Dense populations of Hypogymnia physodes growing frequently as epiphytes on tree branches have harmful effects on the host, likely due to their secondary compounds, which were undetected in tree tissues until now. The aim of the present study was to re-characterise the suite of secondary metabolites of H. physodes thalli and to estimate their translocation into spruce (Picea abies) bark. Thallus and bark extracts were compared using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The compounds were identified based on their UV, MS and MS/MS spectra as well as retention factors of their TLC analysis. In addition to the previously described secondary metabolites (protocetraric, physodalic, 3-hydroxyphysodic, physodic, and 2'-O-methylphysodic acids, atranorin and chloroatranorin) of H. physodes, further three were identified in its thalli: conphysodalic, 4-O-methylphysodic and α-alectoronic acids. Fragmentation patterns from the negative ionisation of each compound were proposed, some of which were described for the first time. Among all of the detected lichen substances, a few, e.g., physodalic, 3-hydroxyphysodic, physodic acids and atranorin, were present in the bark of spruce branches that were abundantly colonised by lichen. The newly identified compounds of H. physodes thalli may belong to its constant or accessory secondary metabolites. These compounds may be useful in the chemotaxonomic classification of this species. The presence of some lichen substances in spruce bark confirmed their ability to penetrate host tissues. These data suggest that H. physodes compounds may cause long-term effects on spruces in nature.

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This paper describes two simple, specific, accurate, and precise methods for estimation of olopatadine hydrochloride (OLO) in tablet dosage form. The first method is a stability-indicating isocratic RP-HPLC method. The analysis is performed on an RP-18 column using 0.1% orthophosphoric acid (adjusted to pH 4.5 with triethylamine)-acetonitrile (75 + 25, v/v) mobile phase at a flow rate of 1 mL/min. Paracetamol (PAR) was selected as the internal standard. Retention times of OLO and PAR were 11.30 +/- 0.02 and 4.70 +/- 0.03 min, respectively. For the HPTLC method, precoated silica gel 60 F254 aluminum sheets were used as the stationary phase; the mobile phase was methanol-chloroform-ammonia (8 + 2 + 0.1, v/v/v). The detection of the analyte band was carried out at 301 nm, and its Rf value was 0.46 +/- 0.03. The analytical methods were validated according to International Conference on Harmonization guidelines. Linear regression analysis data for the calibration plots showed a good linear relationship between response and concentration in the range of 0.1-1 microg/mL and 0.1-0.9 microg/band for HPLC and HPTLC, respectively.

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A sensitive and selective high-performance liquid chromatographic method with fluorescence detection is described for the determination of AJ-3941 (I), a possible agent for the treatment of cerebrovascular disorders, in plasma and brain tissue. A simple hexane extraction was used for plasma, and for brain homogenate the hexane extract was further purified by solid-phase extraction. The determination limit was ca. 3 ng/ml for both plasma (0.5 ml) and 10% (w/v) brain homogenate (1 ml). The method was applied to the determination of I in plasma and brain samples of experimental animals.

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The physico-chemical properties of trans-5-chloro-2-methyl-2,3,3a,12b-tetrahydro-1H- dibenz[2,3:6,7]oxepino[4,5-c]pyrrolidine maleate (Org 5222), a new potential antipsychotic compound, were studied by interpretation of its spectra (UV,IR,NMR,mass), X-ray analysis, thermal properties, solubilities and partition coefficient. Analytical methods such as GLC and TLC were developed for use in stability tests. Crystalline Org 5222 was shown to be stable with respect to heat. Only excessive exposure to light was shown to induce degradation of crystalline Org 5222. In solutions of pH 1, 4 and 7 only slight degradation was observed at high temperature or after exposure to light.

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The metabolism of trans-5-chloro-2-methyl-2,3,3a,12b-tetrahydro-1 H-dibenz[2,3:6,7]oxepinol [4,5-c]pyrrolidine maleate (Org 5222) labelled with [3H] or [14C] was investigated in Wistar rats. Metabolites were identified by mass spectrometry, 13C- and 1H-NMR analysis, IR spectroscopy and, wherever possible, by comparison with authentic reference compounds. The metabolites found in plasma, bile, faeces and urine revealed the processes of metabolism in which Org 5222 underwent oxidation to yield an N-oxide existing in two diastereoisomeric forms, or N-demethylation to yield a demethyl metabolite. A novel metabolite was found in bile, viz. a carbamate glucuronide, formed from an intermediate carbamic acid, derived from the addition of CO2 to the demethyl metabolite.

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The biotransformation of the positively inotropically active compound N-methyl-N-(2-hydroxy-3-phenoxy-propyl)-11-(2-aminoethyl)-6,11- dihydrodibenz[b,e]-oxepine, neutral fumarate, (Doxaminol, racemic mixture of diastereomeres) in dogs is examined. The metabolits M1-M7 were isolated and their chemical structures identified by 1H-NMR, 13C-NMR and mass spectroscopic methods. 2-Hydroxy-3-phenoxypropionic acid, phenoxyacetic acid, 3-(4'-hydroxy)-phenoxy-1,2-propandiol and phenylacetic acid were formed by side chain oxidation of the parent molecule. Furthermore, the following conjugates were characterized: Doxaminol-O-glucuronide, 4'-hydroxydoxaminol-O-glucuronide, and 1-hydroxy-3-phenoxy-2-propyl sulfate.

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A sensitive and specific method is described for the quantitative analysis of 6,11-dihydro-11-oxo-dibenz[b,e]oxepin-3-acetic acid (oxepinac) in human plasma, urine and saliva. Oxepinac and internal standard are extracted from acidified plasma, urine or saliva, converted to the corresponding n-propyl esters and analysed by gas chromatography--mass fragmentography using selected ion monitoring. The method is accurate and precise over the range 100 microgram/ml to 1.0 ng/ml. The method has been applied to the analysis of plasma, urine and saliva from healthy volunteers receiving therapeutic doses of oxepinac.

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A method is described for the quantitative analysis of 6,11-dihydro-11-oxo-dibenz[b,e]-oxepin-2-acetic acid (isoxepac) in plasma and urine. Isoxepac and internal standard was analysed by gas-liquid chromatography using a flame ionization detector. The method is accurate and precise over the range 0.1--30 microgram/ml. The method has been applied to the analysis of plasma and urine from both healthy volunteers and patients receiving therapeutic oral doses of isoxepac.

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Phenothiazines and butyrophenones are known to alter dopamine (3,4-dihydroxyphenethylamine) metabolism in the brain in a fashion suggesting that they may block dopamine receptors. We observed, using Dreiding molecular models, that dopamine in its solid-state conformation is superimposable upon a portion of the known x-ray structure of chlorpromazine [2-chloro-10-(3-dimethylaminopropyl)-phenothiazine]. The ability of phenothiazine drugs to mimic the dopamine-like conformation correlates with their antischizophrenic efficacy. These structure-activity relationships explain the importance of a substituent in ring a, a three-carbon side chain bearing the amino group, and a hetero atom between rings a and c.

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