Synthesis of Novel 1-Arylsulfonyl-4-（1＇-N-2＇, 3＇, 4＇, 6＇-tetra-O-acetyl-β-D-glucopyranosyl）thiosemicarbazides

The synthesis of novel 1-arylsulfonyl -4- （1＇-N -2＇, 3＇, 4＇, 6＇-tetra-O-acetyl-β-D-gluco- pyranosyl） thiosemicarbazides via condensation of 2, 3, 4, 6-tetra-O-acetyl-β-D-glucopyranosyl isothiocyanate with substituted phenylsulfonyl hydrazines was described. Their structures and physical properties were confirmed by ^1H NMR, ^13C NMR spectra, elemental analysis and MS.     

Synthesis and Biological Activity of Novel 2,3-Dihydro-2-phenylsulfonylhydrazono-3-(2′,3′,4′,6′-tetra-O-acetyl-β-D-glucopyranosyl)thiazoles

A series of novel 2,3-dihydro-2-phenylsulfonylhydrazono-3-(2',3',4',6'-tetra-O-acetyl-β-D-glucopyranosyl) thiazoles were designed and synthesized via the reaction of thiosemicarbazide with chloroaldehyde.Their chemical structures were characterized by 1H and 13C NMR spectroscopy and elemental analysis.The bioassay results indicate that some of these compounds exhibit moderate fungicidal and herbicidal activities.     

Synthesis of 3-(3′-Acetyl-5′-aroyl-1′,3′,4′-oxadiazolyl-2′)-chromones

A general method has been proposed for synthesizing 3-(3-acetyl-5-aroyl-1,3,4-oxadiazolyl-2)-chromones that has been based on conversion of 3-formylchromones to acylhydrazones and of theacylhydrazones into the heterocyclic chromones.     

An Improved Synthesis of 2′-Hydroxy-3′,4′,6′-trimethoxyacylophenones

A wide variety of 2′-hydroxypolymethoxyacetophenones and propiophenones, e.g. 1a and 1b are used in the synthesis of flavone and ehromone natural products.¹ Repeated attempts to prepare 1a and 1b by reacting 1,2,3,5-tetramethoxybenzene 2 with acetyl or propionyl chlorides and AlCl₃ in ether² gave products which were difficult to purify.³ We traced the problem to ring-ethoxy contaminants which were isolated and tentatively identified as 3a and 3b.     

Synthesis of Steroidal Spiro-1′,2′,4′-triazolidine-3′-thiones

Steroidal ketone thiosemicarbazones (4–6), obtained from the corresponding ketones(1–3), on oxidative cyclization with H₂O₂ at 0°C provide title compounds (7–9), respectively. The structures of these compounds have been established on the basis of their elemental analytical and spectral data.     

Efficient Synthesis of 1‐(5′‐Acylamino‐1′,3′,4′‐thiadiazol‐2′‐yl)‐4‐acyl‐thiosemicarbazides

Acyl chlorides reacted with ammonium thiocyanate and carbonic dihydrazide under phase‐transfer catalysis to first afford 2,2′‐bis(acylaminothiocarbonyl)‐carbonic dihydrazides, which further cyclized in the presence of glacial acetic acid to efficiently give 1‐(5′‐acylamino‐1′,3′,4′‐thiadiazol‐2′‐yl)‐4‐acyl‐thiosemicarbazides in high yield.     

Synthesis and mesomorphic properties of 4-methoxyphenyl 4′- n -alkoxy-2′,3′,5′,6′-tetrafluorobiphenyl-1-carboxylates

A novel type of 4-methoxyphenyl 4′-n-alkoxy-2′,3′,5′,6′-tetrafluorobiphenyl-1-carboxylates have been synthesized. Textural observations by polarizing microscopy and DSC measurements of the phase transitions show that all of these compounds are thermotropic liquid crystals with only a nematic mesophase. The relationship between the properties and chemical structures of these compounds is discussed.     

Synthesis of New 2′-(2- and 3-Aminopropanoyl)-6′,7′-dimethoxy-2′,3′-dihydro-1′H-spiro[cyclopentane-1,4′-isoquinoline]-1′-carboxamides

Russian Journal of Organic Chemistry - 6′,7′-Dimethoxy-N-methyl-2′,3′-dihydro-1′H-spiro[cyclopentane-1,4′-isoquinoline]-1′-carboxamide reacted with...     

Synthesis of N-Aryl-2-(1′,6′-dihydro-6′-pyridazinone-3′-carbonyl) Thiosemicarbazides and Their Related Heterocyclic Compounds

Introduction Somepyridazineshavebeenexaminedforac- tivityagainstsporozoanandflagellateparasitesand forantiamebicactivity[1]. 6-Aryl-4,5-dihydro-3(2H)-pyridazinonesex- hibitvariousbiologicalpropertiesincludingreduc- tionofbloodpressure,inhibitionofplateletaggre- gation,antiinflammation,andstrongplateletag- gregationinhibitingactioncoupledwithahypoten- siveaction.Italsopossessesweakpositiveinotrop- icactivityforthemanagementofcongestiveheart failure.Threepara-substitueddihydropyridazi- nonesare…     

A Novel Fused Phosphorus Heterocycle: 4-(1′, 2′, 3′, 4′-Tetrahydro- 1, 3, 2-benzodiazaphosphorin-2′-sulfide)-3, 4b, 4a- thiazphosphaphenanthridine Derivative

The first example of fused phosphorus heterocyclic 4-[ l′-(β-bromoethyl)-4'-oxo-3'-prop yl-1′, 2′, 3′, 4-tetrahydro-1, 3, 2-benzodiazaphosphorin-2′-sulfide]-1, 2, 3, 4, 4a, 4b, 5, 6-octahydro -6-oxo-5-propyl-3, 4b, 4a-thiazphosphaphenanthridine 4a, 2′-dioxide was synthesized in excellent yield by refluxing a mixture of 1-(2-bromoethyt)-2, 3-dihydro-3-propyl-l, 3, 2-benzodiazaphos phorin-4(1H)-one 2-oxide with carbon disulfide in benzene in the presence of triethylamine.     

Transition metal(II) complexes of 1-(α-hydroxynaphthyl)-2-(3′-methyl-5′-mercapto-1′,2′,4′-triazole)-2-aza-ethane

Summary Binuclear metal complexes of the type [M(HMTE)-(H₂O)₂]₂, where HMTE=1-(-hydroxynaphthyl)-2-(3-methyl-5-mercapto-1,2,4-triazolc)2-aza-ethane and M-Cu^II, Co^II, Ni^II and Mn^II have been prepared and characterized. An octahedral geometry around the metals is proposed. The complexes have been screened as possible fungicides.     

Synthesis of 3′,4′-Dimethoxyisoflavone Derivaties

2-(Un)substituted-3,4-dimethoxy-7-hydroxyisoflavones were synthesized. Their derivatives substituted at the phenolic hydroxyl were prepared by alkylation and acylation. Aminomethyl derivatives were also prepared.     

Synthesis of 2′-5′,3′-5′ linked triadenylates

2′-5′,3′-5′ Linked triadenylates have been synthesized by direct bisadenylylation of adenosine 2′ and 3′ hydroxyls with an adenosine 5′-phosphorochloridite followed by oxidation.     

Synthesis,structure, and physico-chemical properties of 3-methyl and 3,3-dimethyl derivatives of l-(4′,4′-dimethyl-2′,6′-dioxocyclohex-1′-yl)-3,4-dihydroisoquinoline

3,3-Dimethyl- and 3-methyl-1-(4,4-dimethyl-2,6-dioxocyclohex-1-yl)-3,4-dihydroisoquinolines have been synthesized. Crystal and molecular structures of the 3,3-dimethyl derivative have been determined. In the crystalline state this compound exists as a tautomeric form where a hydrogen atom is located at the N atom of the dihydroisoquinoline fragment of the molecule. The tautomeric equilibrium does not shift noticeably in solutions, as shown by IR, UV, and NMR spectroscopy.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 331–336, February, 1993.     

Stereoselective synthesis and absolute configuration of (1′R,3R,4R)-4-acetoxy-3-(2′,2′,2′-trifluoro-1′-hydroxyethyl)azetidin-2-one

The title compound 3, an intermediate in the synthesis of fluorocarbapenems, is obtained with high stereocontrol by the condensation of (R)-(+)-ethyl 4,4,4-trifluoro-3-hydroxybutanoate with N-trimethylsilyl cinnamylidenimine. X-Ray diffraction analysis of the condensation product and chemical correlations allowed the unambiguous determination of the absolute configuration.     

Synthesis of 2′,3′-Dideoxy-2′-Fluorokanamycin A

2′,3′-Dideoxy-2′-fluorokanamycin A (23) was prepared by condensation of 6-azido-4-0-benzoyl-2,3,6-trideoxy-2-fluoro-α-D-ribo-hexopyranosyl bromide (13) and a protected disaccharide (19). Methyl 4,6-0-benzylidene-3-deoxy-β-D-arabino-hexopyranoside (5) prepared from methyl 4,6-0-benzylidene-3-chloro-3-deoxy-β-D-allo-hexopyranoside (1) by oxidation with pyridinium chlorochromate followed by reduction with Na₂ S₂O₄ was fluorinated with the DAST reagent to give methyl 4,6-O-benzylidene-2,3-dideoxy-2-fluoro-β-D-ribo-hexopyranoside (7). Successive treatment of 7 with NBS, NaN₃ and SOBr₂ gave 13. The structure of the final product (23) was determined by the ¹H and ¹⁹F and shift-correlated 2D NMR spectra.     

X-ray diffraction study of 1,5-bis-(4′,4′,4′-trifluoro-1′-methyl-3′-oxo-but-1′-enylamino)-3-oxapentane

Specific features of the molecular and crystal structures of 1,5-bis-(4′,4′,4′-trifluoro-1′-methyl-3′-oxo-but-1′-enylamino)-3-oxapentane are determined by single crystal XRD.