The synthesis of both 2ʹ-hydroxy-3ʹ-deoxy and 2ʹ-deoxy-3ʹ-hydroxy cyclopentyl nucleoside phosphonates with the natural nucleobases adenine, thymine, cytosine and guanine from a single precursor has been performed. The guanine containing analogues showed antiviral activity. Especially the 3ʹ-deox...

Zusammenfassung2,2,6,6-Tetrakis-(p-toluolsu]fonyloxymethyl)-cyclohexanon (1) liefert bei der Solvolyse in wassrig-alkoholischer Natronlauge als Hauptprodukte die 1-Alkoxymethyl-3-methylencyclohexan-carbonsäuren-(1) 3a–8a und 2-[2-Alkoxymethylcyclopenten-(1)-yl-(1)]-propionsäuren 9a–14a; in t-B...

Recently, 1-(1,4-dioxaspiro[4,5]dec-2-ylmethyl)-4-(2-methoxyphenyl)piperazine (1) was reported as a potent 5-HT1AR agonist with a moderate 5-HT1AR selectivity. In an extension of this work a series of derivatives of 1, obtained by combining different heterocyclic rings with a more flexible amine...

Enantioselective total synthesis of (+)-epiepoformin 1, (+)-epiepoxydon 2 and (+)-bromoxone 3 using a chiral building block, ethyl (1R,2S)-5,5-ethylenedioxy-2-hydroxycyclo- hexanecarboxylate 6, is described. Since the synthesis afforded intermediates 18, 2 and 25, it accomplished a formal synthe...

We examined ten strains of cultured whole-cell yeasts for the asymmetric reduction of commercially available ethyl 2-oxocyclohexanecarboxylate, and found that the (1S,2S)-stereoisomer of ethyl 2-hydroxycyclohexanecarboxylate was the major stereoisomer produced by Williopsis californica JCM 3600....

Alkylation and decarboxylation of α-fluoro-β-ketoesters such as ethyl 2-fluoro-3-oxobutanoate offers a versatile route to a range of fluoro-ketoalkenes, demonstrating the synthetic utility of using α-fluoro-β-ketoesters as synthons for the preparation of synthetically more sophisticated sele...

An enantioselective approach to the synthesis of the hexahydronaphthalene nucleus of natural compactin is described. The key elements of the synthesis are as follows: (i) the preparation of the chiral starting material through enzymatic resolution of the readily available cis 2-methyl-4-oxocyclo...

A coupled achiral-chiral liquid chromatographic assay has been developed to determine the concentrations of metyrapone and the enantiomers of its chiral metabolite metyrapol in plasma and urine. The chromatographic system consisted of a silica precolumn (75 × 4.6 mm I.D.) coupled in-line to a 2...

A sensitive high-performance liquid chromatographic (HPLC) method for the analysis of metyrapone [2-methyl-1,2-di-(3-pyridyl)-1-propanone], its reduced metabolite metyrapol and metyrapone mono-N-oxide metabolites in biological fluids is reported. These components were extracted into dichlorometh...

Copper(II) complexes of a N-octylated bisbenzimidazolyl ligand are synthesized and characterized. These complexes carry out the oxidative dealkylation of 2,4,6-tri-tertbutylphenol (TTBP) using molecular oxygen to 2,6-ditertbutylbenzoquinone and 4,6-di-tertbutylbenzoquinone. The oxidation proceed...

Two-dimensional (2D) early transition metal carbides and/or nitrides (MXenes) have shown significant potential in a wide variety of applications. The majority of MXene research has utilized aqueous colloidal dispersions of MXenes because of the unique hydrophilicity of the MXene surface. In some...

The hydrostannation reaction of various fluoroalkylated acetylene derivatives with tributyltin hydride was investigated using a variety of catalysts in toluene. Among them, the Et3B-induced hydrostannation reaction gave the highest regio- and stereo-selectivity. Their selectivity was mostly infl...

Dialkyl(dimethylphenylsilyl)zinclithium adds effectively to internal acetylenes as well as terminal acetylenes in the presence of CuCN catalyst.

Dialkyl(dimethylphenylsilyl)zinclithium and trialkyl(dimethylphenylsilyl)aluminiumlithium add effectively to internal acetylenes as well as terminal ones in the presence of transition-metal catalysts to provide vinylsilanes with high stereo- and regioselectivities.

The compound, 2,2,3,3-tetramethyl-1,1-bis(dimethylphenylsilyl)silacyclopropane (1), is a potential photochemical source of silylenes either through a 2 + 1 fragmentation of the silacyclopropane ring core or through α-elimination from the aryltrisilane chain. Upon 254 nm photolysis, the silacycl...

The reductive trimethylsilylation of 1,4-bis(trimethylsilyl)benzene to 1,3,4,6-tetrakis(trimethylsilyl)-1,4-cyclohexadiene(III) and of p-dibromo- and p-dichlorobenzenes to (III) and in addition to 1,4,5,6-tetrakis(trimethylsilyl)-1,3-cyclohexadiene(IV) and 3,3,6,6-tetrakis(trimethylsilyl)-1,4-cy...

A series of polykis(pyrazol-1-yl)benzenes, potential chelating ligands for transition metals, have been prepared by nucleophilic substitution of fluorine in 1,2-difluoro-, 1,2,3,4-tetrafluoro-, 1,2,4,5-tetrafluoro-, and hexafluorobenzenes. The observed substitution pattern indicated formation of...

The crystalline compound [K([18]crown-6){C6H4(SiMe3)2-1,4}] (1) was prepared by the low-temperature reduction of the para-disilylated benzene with K/[18]crown-6 in toluene followed by recrystallisation from the same solvent. Reduction of 1,2,4,5-tetrasilylated benzene with 2(K/[18]crown-6) in to...

The reaction of 1,3,5-tribromo- or 1,2,4,5-tetrabromobenzene with trimethylstannyl sodium in tetraglyme gave the corresponding polystannylated benzene derivatives 2 and 4, respectively, in high yield. They were converted with mercuric chloride to the corresponding tris- and tetrakis(chloromercur...

The cyclotrimerization of 1-phenyl-2-(trimethylsilyl)acetylene (PTMSA) catalysed by the TiCl4/Et2AlCl (Ti: Al = 10–20) system affords 1,3,5-triphenyl-2,4,6-tris(trimethylsilyl)benzene (I) (minor product) and ethyl-triphenyl-bis(trimethylsilyl)benzene (II) (major product) in low yields. An X-ray...