34905-87-8

Upstream product

• 124938-46-1 C₈H₁₁ClHgO₂ 
• 54565-98-9 (-)-bicyclo[4.2.0]oct-3-en-8-one 
• 3675-31-8 2-(cyclohex-2-enyl)acetic acid 
• 34939-28-1 dimethyl 2-(cyclohex-2-en-1-yl)malonate 
• 6253-27-6 4,5-epoxy-cyclohexene 
• 1165952-92-0 cyclohexa-1,4-diene 

Relevant academic research and scientific papers

Stereoselective synthesis of deoxycarbaheptopyranose derivatives: 5a-carba-6-deoxy-α-dl-galacto-heptopyranose and 5a-carba-6-deoxy-α- dl-gulo-heptopyranose

Two new deoxycarbaheptopyranoses, 5a-carba-6-deoxy-α-dl-galacto- heptopyranose and 5a-carba-6-deoxy-α-dl-gulo-heptopyranose were prepared starting from cyclohexa-1,4-diene. The addition of dichloroketene to cyclohexa-1,4-diene followed by the subsequent reductive elimination and Baeyer-Villiger oxidation in turn led to the formation of a bicyclic lactone. Reduction of the lactone moiety followed by acetylation gave a diacetate with cis-configuration. The introduction of additional acetate functionality into the molecule was achieved by singlet oxygen ene-reaction. The formed hydroperoxide was reduced and then acetylated. The triacetate was further functionalized either by direct cis-hydroxylation using OsO4 or by epoxidation followed by a ring-opening reaction to give the title heptopyranose derivatives. One of the synthesized molecules, galacto-heptopyranose exhibited enzyme specific inhibition against α-glycosidase. On the other hand, they did not show any inhibition for α-amylase. However, both compounds, gulo-heptopyranose and galacto-heptopyranose increased the activity of α-amylase.

Enantioselective total synthesis of virosaine A and bubbialidine

The first enantioselective total syntheses of virosaine A and bubbialidine are described. Key transformations include the formation of a tetracyclic intermediate via an intramolecular aza-Michael addition, generation of a N-hydroxy-pyrrolidine through a Cope elimination and an intramolecular [1,3]-dipolar cycloaddition to generate a complex 7-oxa-1-azabicyclo[3.2.1] octane ring system. The Royal Society of Chemistry 2013.

The synthesis of monocyclic and bicyclic molecules and their antioxidant properties

The synthesis and antioxidant activity of novel cyclitol, lactone and epoxide derivatives starting from appropriate 1.4-cyclohexadiene are reported in this study. All structures of these products were characterized by 1H NMR, 13C NMR, MS and IR spectroscopy. The antioxidant capacities of some synthesized compounds were studied by using the methods of the scavenging effect on DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals. It is seen that the antioxidant properties of two of the five synthesized molecules were close to α-tocopherol.

Enantio-differential approach using fluorescence-labeled phyllanthurinolactone, a leaf-closing factor of Phyllanthus urinaria L.

We report here the synthesis of enantio-pair-type fluorescence-labeled probes based on phyllanthurinolactone (1), which is a leaf-closing substance of Phyllanthus urinaria L. Moreover, the application of an enantio-differential approach to distinguish bet

Oxidative cyclizations in a nonpolar solvent using molecular oxygen and studies on the stereochemistry of oxypalladation

Oxidative cyclizations of a variety of heteroatom nucleophiles onto unactivated olefins are catalyzed by palladium(II) and pyridine in the presence of molecular oxygen as the sole stoichiometric oxidant in a nonpolar solvent (toluene). Reactivity studies of a number of N-ligated palladium complexes show that chelating ligands slow the reaction. Nearly identical conditions are applicable to five different types of nucleophiles: phenols, primary alcohols, carboxylic acids, a vinylogous acid, and amides. Electronrich phenols are excellent substrates, and multiple olefin substitution patterns are tolerated. Primary alcohols undergo oxidative cyclization without significant oxidation to the aldehyde, a fact that illustrates the range of reactivity available from various Pd(II) salts under differing conditions. Alcohols can form both fused and spirocyclic ring systems, depending on the position of the olefin relative to the tethered alcohol; the same is true of the acid derivatives. The racemic conditions served as a platform for the development of an enantioselective reaction. Experiments with stereospecifically deuterated primary alcohol substrates rule out a "Wacker-type" mechanism involving anti oxypalladation and suggest that the reaction proceeds by syn oxypalladation for both mono- and bidentate ligands. In contrast, cyclizations of deuterium-labeled carboxylic acid substrates undergo anti oxypalladation.

Synthesis of phyllanthurinolactone, the leaf-closing factor of Phyllanthus urinaria L., and its three stereoisomers

Phyllanthurinolactone (1) and its three stereoisomers 18-20 were synthesized, and only 1 was bioactive as the leaf-closing factor of a nyctinastic plant, Phyllanthus urinaria L. X-ray analysis of the tetraacetylglucoside 17 was executed, and the absolute configuration of 1 was determined as 6S,7aR.

Synthesis and absolute configuration of phyllanthurinolactone, the leaf- closing factor of a nyctinastic plant, Phyllanthus urinaria L.

Phyllanthurinolactone (1) and its diastereoisomer 19 were synthesized, only the former of which was bioactive as the leaf-closing factor of Phyllanthus urinaria L. X-ray analysis of the tetraacetylglucoside 18 was executed, and the absolute configuration of 1 was determined as 6S, 7aR.

Unusual facial selectivity in the cycloaddition of singlet oxygen to a simple cyclic diene

Syntheses of 5-isopropyl-1,3-cyclohexadiene and syn-5-isopropyl-2,3-dioxabicyclo[2.2.2]octane, by routes that would allow completely diastereoselective introduction of deuterium labels, are described. The reaction of the isopropyl cyclohexadiene with singlet oxygen is shown to give an endoperoxide that is derived by preferential attack on the more sterically hindered face of the diene. A possible mechanistic explanation of this result is that the attack from the less hindered face leads to "ene" reaction rather than endoperoxide formation. However, this mechanism would require that the "ene" reaction and cycloaddition proceed via a common intermediate-presumably a perepoxide.

Highly Enantiospecific Synthesis of 4-Alkyl and 4,5-Dialkyl Substituted 4,5-Dihydrofuran-2(3H)-ones from Optically Active (E)- and (Z)-Alk-1-enyl p-Tolyl Sulphoxides: Application to the Synthesis of Lignan Lactones

Stereochemically and optically pure 2-substituted ethylenic p-tolyl sulphoxides (R)-E-(4) and (R)-Z-(4) undergo readily and stereospecifically an additive Pummerer rearrangement reaction with dichloroketene to give trans- and cis-β-alkyl-α,α-dichloro-γ-p-tolylthio-γ-butyrolactone derivatives (5), respectively.Sequential reductive dechlorination and desulphurization lead to (-)-(S)-, from trans-(5), and (+)-(R)-β-alkyl-γ-butirolactones (7), from cis-(5), with a high optical purity, respectively.Reaction of the intermediate tolylthio derivatives (6) with allyltributylstannane gives β-alkyl-γ-allyl-γ-butyrolactones (15) and (16).These sequential reactions can be successfully applied to the synthesis of (+)-(R)-β-piperonylbutyrolactone (20), the key intermediate for the synthesis of antileukemic lignan lactones, in high chemical and optical yields.Acylation of compound (20) with 3,4,5-trimethoxybenzoyl chloride furnishes (+)-podorhizon (21).

SYNTHESIS OF UNSATURATED BICYCLIC LACTONES AND ACETALS VIA PALLADIUM-PROMOTED CYCLIZATION OF CYCLIC ALLYLIC ALCOHOLS

Unsaturated bicyclic lactones are readily prepared by converting cyclic allylic alcohols to the corresponding α-chloromercurio acetate esters and reacting them with Li2PdCl4.The corresponding acetals can be synthesized directly by reaction of the allylic