Other Heterocyclic Derivatives

Pyrrole derivatives (e.g., 36) were prepared by cycllzation of keto-enamlnes prepared from 2-amino-2-deoxyheptoses.Dehydrative cycllzations of D-gluco- or D-manno-pentltol-l-yl-heterocycles Initially gave the same a-D-arabinofuranosyl derivatives (e.g., 37) which then rearranged to their more stable a-pyranosyl analogues in contrast, D-galacto-pentltol-1-yl heterocycles formed anomeric D-lyxopyranosyl derivatives directly due to the strained nature of 

The D-arabino-tetrltol-l-yl pyrazlne derivative (38) has been synthesized by treatment of a 2-amino-2-deoxy-D-glucose oxime - 

4-Bls(4H-benzoxazin-4-one-2-yl)-galacto-tetritol tetraacetate (42) was obtained by condensation of anthranilic acid with the 

Dipolar cycloaddltlon of diphenylnitrile imlne (PhN-N=JPh) with a 2,3-unsaturated sugar derivative gave a 4 1 mixture of the 

Horlkawa, M.Ozeki, N.tknino, M.Kawamorl, Y.Arai, and K.Tsujihara, Chem. Pharm. Bull., 1982, 30, 534. 

Alditol-l-yl-pyrazole derivatives have been synthesized by condensing aminosugars with B-diketones and related compounds. 

Further 2-(alditol-l-yl)-l-alkyl-4,5,6,7-tetrahydroindol- l-ones have been obtained from 2-alkylamino-2-deoxy-hexoses and -heptoses with 5,5-dimethyl-l, 3-cyclohexadione (c.f. Vol.l7, p.113).  

While a 2-(D-arabino-tetritol-l-yl)-l-methylpyrazole derivative was obtained from the condensation of 2-deoxy-2-methylamino-D-glucose with ethyl acetoacetate (c.f. Vol.l4, p.89), the 3-substituted pyrrole analogues (72) were obtained from 1-deoxy-l-raethylamino- 

D-arabino- and -lyxo-hex-2-uloseswlth ethyl acetoacetate or pentane-7c 

i -dione. Condensation of l-amlno-l-deoxy-D-lyxo-hex-2-ulose with phenyl isothiocyanate yielded the acyclic imidazole-2-thione 

Spiro- and blcyclo-nucleoside analogues have been obtained as 

Various iraidazole-2-thiones ( 7) have been obtained from the condensation of 1-alkylamino-l-deoxy-D-fructoses with methyl or phenyl isothiocyanate (c.f. Vol.19, p.ll3).  

The conformational changes induced by 0-acetylation of the poly-hydroxyalkylpyrazoloC3, i)-b]quinoxalines ( 8) have been studied by %-n.m.r. and c.d. spectroscopy they are considered to be due to 

Lopez Garzon, M.Nogueras Montiel, A.Semchez Rodrigo, J.Negrillo Perez, and A.M.Bemalte Garcia, Thennochim. Acta, 1985, 91, 173 (Chem. Abstr., 1986, 

Babiano Caballero, J.Puentes Mota, amd J.A.Galbis Perez, Carbohydr. Res., 1986, 154, 280. 

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The photoelectron spectrum of selenophene vapor down to 1350 A has been studied. By analogy with the other heterocyclic derivatives, Rydberg-type transitions occur, leading to the first ionization potential of the molecule.23... 

IV. Other Heterocycles Derived from l,6,6a1S IV-Trithiapentalenes... 

It is noteworthy that in the tribenzcycloheptatriene series, the replacement of a —CH2— group with an > SiMe2 group does not result in a decrease in the barrier to ring inversion in direct contrast to the previously discussed silacyclohexane system (77). There now exist two extremes in ring flexibility for silicon compounds. It is necessary to study other heterocyclic derivatives before it will be possible to evaluate the effect on ring flexibility with heteroatom replacement. 

In the course of the Schering calcitriol program a variety of other heterocyclic derivatives were synthesized and investigated. Apart from the oxazole series, thiazole calcitriols were identified as interesting substructures as well. 

Dehydration of the carbohydrate portion in fiuctosamines probably proceeds through a series of enolic intermediates (Scheme 31), whieh eventually tautomerize into a-dicarbonyl stractures such as 60, 62, and 63, or cycUze into 2-furoylmethyl-amines (61) and many other heterocyclic derivatives. One of the major products of D-fructosamine degradation that occurs through the 1,2-enoUzation pathway is 3-deoxy-D-e 7 /jro-hexos-2-ulose (60), which is regarded as one of the most important intermediates in the Maillard reaction both in foods and in vivo ... 

Nitriles, Isonitriles, Oximes, and Hydroxylamines Hydrazones, Osazones, and Derived Heterocycles Other Heterocyclic Derivatives... 

Imidazolidine and imidazoline derivatives were formed when dialdose derivatives reacted with 2,3-bis(hydroxylamino)-2,3-dimethylbutane (Scheme 60) oxidation of these derivatives afforded stable free radicals that were examined by e.s.r. spectroscopy. Several oxazole and thiazolidine derivatives having C-5 and C-6 of 3-0-benzyl-l,2-0-isopropylidene-jS-L-idofuranose as part of the heterocyclic ring, and a new class of bicyclic thiazolidine derivative (172) have been prepared by the reactions shown in Scheme 61. The bis(l,3,4-oxadia-zole) derivative (173) has been prepared by condensative cyclization of 2,3,4,5-tetra-O-acetylgalactaric acid bis(benzoylhydrazide) with triethyl orthoformate in p-dioxan. Other heterocyclic derivatives are referred to in Chapters 14 and 15. 

Other heterocyclic derivatives of juglone with antibiotic properties, namely, frenocilin 189 were isolated from cultures of Streptomyces roseofulvus and Streptomyces respectively (05MI214)... 

The cycloadducts formed from glycals and dibenzyl azodicarboxyl-ate, anomalously linked nucleosides from 2-deoxy-D-ribose, and certain other heterocyclic derivatives are covered in Chapter 9. 

Kocienski and co-workers discovered that metallated 1-phenyl-1//-tetrazol-5-yl sulfones (PT, 6) gave much better yields compared to its BT-substituted counterpart suggesting that the PT sulfone anions are less prone to self-condensation. Other heterocyclic derivatives, such as pyridine-2-yl (PYR, 7), l-tert-butyl-l//-tetrazol-5-yl (TBT, 8), and 3,5-bis(trifluoro-methyl)phenyl (BTFP, 9) sulfones" have also provided useful levels of stereoselectivity in the one-pot Julia-Kocienski olefination reaction. 

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