A Facile Synthesis of Benzoxazolyl Cyclopropanes

2′-Benzoxazolyl substituted cyclopropane derivatives were synthesized in the yield of 73-89% from the reaction of telluronium ylides with chalcones.     

A Facile Synthesis of N γ-Glycosyl Asparagine Conjugates and Short N-Linked Glycopeptides

Both free and protected glycosyl azides were efficiently coupled to the side chain of aspartate by the Staudinger reaction for the synthesis of N ^γ-glycosyl asparagine conjugates and short N-linked glycopeptides that can be employed to construct complex N-linked glycopeptides. In the process, a facile two-step protocol was developed for free glycosyl azide synthesis, which includes reported direct transformation of free oligosaccharides into glycosyl amines through reaction with ammonium bicarbonate and then stereospecific diazo transfer reaction to convert glycosyl amines to glycosyl azides.     

A Facile and Green Synthesis of Sulforaphane

Sulforaphane (1, SFN), 4-methylsulfinylbutyl isothiocyanate, was considered as the most potent inducer of phase II enzymes proteins [glutathione transferases (GSTs) and NAD(P)H: quinone reductase (QR)] selectively, and strong inhibitor of phase I enzymes …     

Hydroamination of Dihapto-Coordinated Benzene and Diene Complexes of Tungsten: Fundamental Studies and the Synthesis of γ-Lycorane

Reactions are described for complexes of the form WTp(NO)(PMe₃)(η²-arene) and various amines, where the arene is benzene or benzene with an electron-withdrawing substituent (CF₃, SO₂Ph, SO₂Me). The arene complex is first protonated to form an η²-arenium species, which then selectively adds the amine. The resulting η²-5-amino-1,3-cyclohexadiene complexes can then be subjected to the same sequence with a second nucleophile to form 3-aminocyclohexene complexes, where up to three stereocenters originate from the arene carbons. Alternatively, 1,3-cyclohexadiene complexes containing an ester group at the 5 position (also prepared from an arene) can be treated with acid followed by an amine to form trisubstituted 3-aminocyclohexenes. When the amine is primary, ring closure can occur to form a cis-fused bicyclic γ-lactam. Highly functionalized cyclohexenes can be liberated from the tungsten through oxidative decomplexation. The potential utility of this methodology is demonstrated in the synthesis of the alkaloid γ-lycorane. An enantioenriched synthesis of a lactam precursor to γ-lycorane is also described. This compound is prepared from an enantioenriched version of the tungsten benzene complex. Regio- and stereochemical assignments for the reported compounds are supported by detailed 2D-NMR analysis and 13 molecular structure determinations (SC-XRD).     

Facile Synthesis of Isoamericanol and Isoamericanin A

A number of benzodioxane compounds were synthesized using the palladium-catalyzed etherification of aryl halides by employing triphenylphosphane ligands. This method was used as key step in the synthesis of isoamericanol A and isoamericanin A.     

A Facile Synthesis of β-Cyclodextrin Monoaldehyde

Cyclodextrinsandtheirderivativeshaveplayedimportantrolesinsuchdiversefieldsaschiralseperation,artificalenZymes,asymmetricsynthesisanddrugdelivery'.ThecyclodextrinmonoaldehydeisanewlydevelopedintermediatetosynthesizenovelderivativesthroughreductiveaminationinthepresenseofsodiumcyanoborohydrideThereportedsynthesisofcyclodextrinmonoaldehydeinvolvedtheoxidationofp-CDmonotosylatebyDMSOinthepresenceofcollidineordiisopropylethylamine",ordirectoxidationofP-CDwithDess-Martinperiodinane(DMP)'.Thel…     

A Facile Synthesis of Indole-based Conjugated Derivatives

A novel synthetic method was developed for the preparation of indole-based conjugated derivatives with satisfied yields. By applying this strategy, a series of new compounds were prepared conveniently. All the obtained new indole derivatives were characterized by spectroscopic analyses, giving satisfactory data corresponding to their expected molecular structures.     

A Facile Synthesis of Squamosamide Cyclic Analogs

A series of novel cyclic derivatives have been synthesized by utilizing a nickel powder mediated radical cyclization as the key step. The structures of the new compounds were confirmed by ^lH-NMR and MS.     

Facile and Efficient Synthesis of γ-Lactone and Butenolide Derivatives

An efficient Baeyer–Villiger rearrangement of cyclobutanone derivatives was investigated. One-pot synthesis of keto-δ-lactone from the Baeyer–Villiger rearrangement products was developed. Meanwhile, the synthetic useful γ-lactone and butenolide derivatives could be easily prepared.     

A Simple Synthesis of γ-Cyclohomocitral

A simple and efficient synthesis for γ-cyclohomocitral (10), a key and versatile intermediate for the synthesis of some furanosesquiterpenes, is described. The formal total synthesis of (±) Pallenscensone (2) was accomplished.     

A Facile Synthesis of N′-Benzoyl Thiophosphoryluras

Twelve title compounds 3a-l were synthesized by nuclophilic addition of thiophosphoramide 1 to benzoylisocyanate 2. The yield of compounds 3a-f and 3g-l is 72–83% and 18–33%.     

A Facile Synthesis of 3,4‐Benzo‐β‐carbolines

Abstract

A convenient method for the synthesis 3,4‐benzo‐β‐carbolines (10) from the corresponding N‐phenylsulfonyl‐3‐bromo‐N′‐arylisogramines (5) via radical mediated cyclization methodology has been reported.     

A Facile Synthesis of N-Substituted Spirocyclic Diester of α-Aminophosphonic Acid

Inl965,RudietaL1rePortedthataspirocycliccompound(3,9-2H-2,4,8,lO-tetraoxa-3,9-diphosPhasPirol5,5lundecane-3,9-disulfide)possessesverygoodherbicidalactivity.Ourrecentresearchzshowedthatsomeix-andnophosphonicacidderivativesalsoexhibitgoodherbicidalachvity.Inaddition,ChrisMeierrecentlyreportedtiutafterfor-mationoftheprodrugwithacyclicphosphorylgroup,thebiologicallyactivenucleosideanalogUewouldovercomethedifficultyoftheintr8cellulardeliverybecauseitiseasierfortheprodrugtopassthrougl1amembranet…     

A Facile Synthesis of N-Phosphoryl Amino Acids Containing Hydroxy Group

three kinds of N-(diisopropyloxyphosphoryl) amino acids containing hydroxyl group were prepared in high yield by using diisopropyl phosphite as the phosphorylating agent, sodium hypochlorite as the chlorinating agent and tetrabutyl ammonium bromide as the phase transfer catalyst in basic aqueous media.     

A Facile Solid—phase Synthesis of 3—Carboxycoumarins

3-Carboxycoumsrins were synthesized via the solid phase synthesis conviently. The resin bound cyclic malonic ester reacted with o-methoxy or o-hydroxybenzaldehydes. Then cyclization was processed under H2SO4 to afford the products in excellent purities and yields.     

A Facile Synthesis of Spin Labeled 4′-Epi-N-Trifuoroactyldaunomycin Derivatives

The anthracycline antibiotics, such as daunomycin 1 and doxorubicin 2, have attracted considerable interest because of their great therapeutic value in treating a number of human cancers. However, their use has been limited by a number of toxic and undesirable side effects and this stimulated the search for new anthracyclines with improved pharmacological profiles1,2,3. In our group, nitroxy radicals were first introduced to the sugar moieties of 1 and 2, and some exhibited significant antitum…     

Synthesis of γ-mercuridinitrohydrocarbons

Summary The denitration of -mercurinitro compounds has been studied and the corresponding organomercury dinitro derivatives have been obtained.     

Facile Method for the Large-Scale Synthesis of 6,7,4′-Trihydroxyisoflavanone

6,7,4′-Trihydroxyisoflavanone, the main source of which is extracted from soybeans, has been found to have diverse significant bioactivities. A large-scale, cost-effective, and facile chemical synthesis of 6,7,4′-trihydroxyisoflavanone is presented herein. Its synthesis is characterized by three steps with an overall yield of 71% and a purity or more than 99.0%. This reaction can be scaled up to multikilogram quantities, providing a solid basis for its further bioactivity studies and drug development. With this same method, 6,7,3′,4′-tetrahydroxyisoflavanone, an analog of 6,7,4′-trihydroxyisoflavanone, also can be largely prepared, indicating this modified synthetic method is potentially available for large-scale synthesis of a broad range of multihydroxyl isoflavanones.     

A Short Synthesis of γ-Lactams Via the Spontaneous Ring Expansion of β-Lactams

β-Lactams, derived via the cycloaddition of chlorosulfonyl isocyanate to alkenes, undergo thermal rearrangement at room temperature to afford γ-lactams.     

Facile Synthesis of bis‐α‐Aminoalkylphosphinates

Herein we report a facile synthesis of esters of bis‐α‐aminoalkylphosphinic acids obtained by an addition of Cbz‐protected phosphinic analogues of amino acid methyl esters to an appropriate imine in refluxing benzene. Complete deprotection of the esters could be achieved in one step by the action of 30% HBr in acetic acid.