Modified Coumarins. 16. Cyclohexane-Annelated Analogs of Pyranocoumarins

Modified derivatives of angular and linear pyranocoumarins containing a condensed cyclohexane moiety were prepared by fusing a 2,2-dimethyltetrahydropyran ring to the coumarin system and annelating a pyrone ring to derivatives of 2,2-dimethylchromane. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 313–318, July–August, 2005.     

Modification of salsoline, salsolidine, and anabasine with dibenzo-24-crown-8-dicarboxylic acid dichloride

New derivatives of dibenzo-24-crown-8-dicarboxylic acid diamide with salsoline, salsolidine, and anabasine moieties were prepared by condensation of the alkaloids with 4′,4″(5″)-dibenzo-24-crown-8-dicarboxylic acid dichloride. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 471–473, September–October, 2006.     

Sesquiterpene Lactones from <Emphasis Type="Italic">Stizolophus balsamita</Emphasis> and Their Biological Activity

Four sesquiterpene lactones with the germacrane structure were isolated from the aerial part of Stizolophus balsamita. X-ray structure analyses showed that two of them were previously known balsamin derivatives. A third was a crystalline isomorphous mixture of the known lactone stizolin and 11,13-dihydrostizolin in a 53:47 ratio. The biological activities of the balsamin derivatives were investigated. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 454–457, September–October, 2005.     

Synthesis of new derivatives of 3<Emphasis Type="Italic">β</Emphasis>-hydroxy18<Emphasis Type="Italic">β</Emphasis>H-olean-9,12-dien-30-oic acid

Ring A was transformed and new A-homo-4-aza- and 3-cyano-3,4-seco-olean-4-ene derivatives of 3β-hydroxy18βH-olean-9,12-dien-30-oic acid were synthesized. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 335–338, May–June, 2009.     

Determination of aspartate and glutamate in rabbit retina using polymer monolith microextraction coupled to high-performance liquid chromatography with fluorescence detection

A simple, sensitive and low-cost method was developed for the determination of aspartate (Asp) and glutamate (Glu) in rabbit retina. Polymer monolith microextraction (PMME) using a poly(acrylamide–vinylpyridine–N,N′-methylene bisacrylamide) (AA–VP–Bis) monolithic column was combined with derivatization of Asp and Glu using 8-phenyl-(4-oxy-acetic acid N-hydroxysuccinimide ester)-4,4-difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diaza-s-indacene (TMPAB-OSu), and this was used to analyze the derivatives of Asp and Glu by high-performance liquid chromatography (HPLC) with fluorescence detection. The conditions for the derivatization and the subsequent extraction of Asp and Glu derivatives were optimized. The enrichment factors for the derivatives of Asp and Glu were found to be 14.1 and 14.7, respectively, by PMME. The limits of detection of Asp and Glu were 0.14 and 0.53 nmol/L, respectively. The precision and recovery were evaluated with spiked retina. The inter- and intraday relative standard deviations were less than 10%. The proposed method was successfully applied to the determination of Asp and Glu levels in rabbit retina samples with different stages of intraocular hypertension.     

Xanthene Derivatives and <Emphasis Type="Italic">ortho</Emphasis>-Substituted Phenols — Products from Dehydrogenation of Acyclic 1,5-Diketones

Xanthene derivatives and ortho-substituted phenols were obtained during the dehydrogenation of 1,5-diketones and their ketol forms at a Pt/C catalyst at 280–320°C. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1637–1643, November, 2005.     

Synthesis of cyasteronylthiocarbamate derivatives

Ecdysterone, cyasterone, ajugalactone, ajugasterone B, 22-acetylcyasterone, and turkesterone were isolated from leaves of Ajuga turkestanica (Labiatae). Their structures were established using spectral and chemical data. The 2,3,22-triacetate, 2,3,22-tri-O-p-iodobenzoylthiocarbamate, and 2-O-p-iodobenzoylthiocarbamate derivatives of cyasterone were synthesized. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 449–451, September–October, 2006.     

Synthesis of 3S-methylundec-1-ylbromide, a key synthon in the synthesis of (S,S,S)-diprionylacetate, from L-(-)-menthol

Three new approaches to the synthesis of 1-bromo-3S-methylundecane, a key synthon in the synthesis of (S,S,S)-diprionylacetate, a sex pheromone of pine sawflies of the genera Diprion and Neodiprion, were proposed based on chemo-and stereoselective transformations of L-(-)-menthol derivatives. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 73–76, January–February, 2006.     

Acidic isomerization of alantolactone derivatives

A series of derivatives of the natural sesquiterpene lactones alantolactone (1) and isoalantolactone (2) was prepared. The α-methylene-γ-lactone moiety was retained in the structures of these for further modifications using reactions that affected exclusively the nonconjugated double bonds of the decalin ring. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 325–330, July–August, 2006.     

Modified lignin with ion-exchange properties

Polyfunctional ion-exchangers were synthesized by heterophase amination of α-oxide derivatives of hydrolyzed lignin with aliphatic di-and polyamines. Optimal conditions for their preparation were determined. Certain physicochemical properties were studied. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 492–495, September–October, 2007.     

Quaternary salts of alkaloids

New biologically active quaternary salts of the alkaloids ajmaline, quinine, hyoscyamine, codeine, and strychnine were synthesized. So-called separable conformers were observed among the ajmaline derivatives. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 381–383, July–August, 2006.     

Reaction of natural isoflavonoids and their analogs with hydroxylamine

Recyclization of the chromone ring in several natural isoflavonoids and their analogs by reaction with hydroxylamine was studied. It has been found that the most suitable base for carrying out the reaction is N-methylmorpholine. Several derivatives of 4-aryl-5-(2-hydroxyphenyl)isoxazole were synthesized. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 332–336, July–August, 2007.     

Stereospecific mannosylations of myo -inasitol: Synthesis of manno- myo -inositol fragment of Mycobacterium tuberculosis

Methyl iodide activated stereospecific α-mannosylations utilising 2-pyridyl-1-thiomannopyranoside derivatives (2,3,4) as donors and suitably protected myo-inositol derivatives (1,25,27,29) as acceptors to prepare 2-0-α-D-mannopyranosyl-6-[O-α-D-mannopyranosyl-(1–6)-O-α-D-mannopyranosyl-(l-6)-O-α-D-mannopyranosyl]-D-myo-inositol derivative (31) is described. IICT Commun. No. 3355     

Mannich reaction in the synthesis of N,S-containing heterocycles. 1. Synthesis of novel derivatives of imidazo[2,1-<Emphasis Type="Italic">b</Emphasis>][1,3,5]thiadiazine

Reactions of (Z)-5-benzylidene-2-thiohydantoin with formaldehyde and primary aromatic amines afforded novel derivatives of imidazo[2,1-b][1,3,5]thiadiazine in 50–69% yields. Dedicated to Academician N. S. Zefirov on the occasion of his 70th birthday. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2158–2160, September, 2005.     

Topological approach in determining the structure-property dependence in a series of 4-cyclohexene-1,2-dicarboxylic acids

Theoretical information indices of cis- and trans-4-cyclohexene-1,2-dicarboxylic acids and their methyl and dimethyl substituted derivatives are calculated. Correlations between the indices and physicochemical properties of these compounds are analyzed. Original Russian Text Copyright ? 2009 by M. S. Salakhov, B. T. Bagmanov, and O. T. Grechkina __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 50, No. 1, pp. 183–187, January–February, 2009.     

An efficient <Emphasis Type="Italic">Mannich</Emphasis>-type synthesis of <Emphasis Type="Italic">bis</Emphasis>(pyrido[2,1-<Emphasis Type="Italic">b</Emphasis>][1,3,5]thiadiazin-7-yl)-methanes

Morpholinium 3-cyano-4-methyl-6-oxo-1,6-dihydropyridine-2-thiolate upon treatment with primary amines and a formaldehyde excess under mild conditions produces bis(pyrido[2,1-b][1,3,5]thiadiazin-7-yl)methane derivatives in good yields (67–87%). Correspondence: Victor V. Dotsenko, State Enterprise “Luganskstandartmetrology”, 91021 Lugansk, Ukraine.     

Synthesis and antituberculotic activity of some new imidazo[4,5-b]pyridine derivatives

The reactions of 2-acetylimidazo[4,5-b]pyridine hydrazone with some alkyl-and arylisothiocyanates and some orthoesters were carried out. Various new derivatives of the titled compound such as thiosemicarbazones, ethoxymethylenehydrazones, and derivatives of the new pyrido-[3′,2′:4,5]imidazo[1,2-d][1,2,4]triazine ring system were obtained. Biological data for selected compounds are presented. Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1571–1579, October, 2006.     

N-glycyl-β-glycopyranosylamines, derivatives of mono- and disaccharides, and their use for the preparation of carboxylic acid glycoconjugates

A convenient preparative procedure was developed for the synthesis ofN-glycyl-β-glycopyranosylamines, derivatives of monosaccharides (d-galactose,d-mannose,l-fucose, andN-acetyl-d-glucosamine) and disaccharides (lactose, melibiose, cellobiose, and maltose). These compounds were demonstrated to be useful for the preparation of glycoconjugates of biologically active compounds containing the carboxy group (nicotinic, orotic, kynurenic, and indoleacetic acids). Synthetic pathways were developed for conversions ofN-glycyl-β-glycopyranosylamines into derivatives containing the carboxy group with the use of malonic andl-tartaric acid derivatives. Published inIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1461–1466, August, 2000.     

Synthesis and NMR spectroscopy investigations of functionalized 8,8,10-trimethyl-4-phenyl-7,8-dihydro-2<Emphasis Type="Italic">H</Emphasis>,6<Emphasis Type="Italic">H</Emphasis>-pyrano[3,2-<Emphasis Type="Italic">g</Emphasis>]chromene-2,6-diones and their spirothiadiazole derivatives

New functionalized derivatives of 8,8,10-trimethyl-4-phenyl-7,8-dihydro-2H,6H-pyrano[3,2-g]-chromene-2,6-dione – analogues of the natural compound graveolone – possessing hydrazine, hydroxylamine, and thiosemicarbazide residues were synthesized and their reactions with acetic anhydride were studied. The structure of the obtained compounds was confirmed by NMR spectroscopy. Correspondence: Viktoria Moskvina, Chemistry Department, Kyiv National Taras Shevchenko University, 60, ul. Vladimirskaya, 01033 Kyiv, Ukraine.     

Isolation and identification of anthraquinones of Caloplaca cerina and Cassia tora

Five hydroxyanthraquinone derivatives physcion, emodin, fallacinal, teloschistin, and 1,3-dimethoxy-8-hydroxy-6-methyl-9,10-anthraquinone were isolated from the lichen Caloplaca cerina growing in Serbia. Three anthraquinone derivatives, namely physcion, emodin, and rhein were isolated and identified from the Thai medicinal plant Cassia tora. Presented at the 33rd International Conference of the Slovak Society of Chemical Engineering, Tatranské Matliare, 22–26 May 2006.