A Novel Synthesis of (-)-10-epi-α-Cyperone

The eudesmane derivative, (-)-10-epi-α-cyperone 1, is widely used as a chiral starting material for the synthesis of other fused-ring sesquiterpenes1. The first synthetic work was reported by Howe and co-workers via condensation of (+)-dihydrocarvone 2 with 1-diethylaminopentan-3-one methiodide in 32% yield2. Previously, our group reported the synthesis of compound 1 by treating ketone 2 with ethyl vinyl ketone (EVK) directly under different conditions1a, but the yields were not satisfacto…     

Synthesis of 14-epi-19-nor-22-oxa-1α,25-dihydroxyvitamin D3

The synthesis of 14-epi-19-nor-22-oxa-1α,25(OH)2D3 5 was started from diol 8 via Fall's method, oxidation, epimerization, protection, coupling with the 19-nor-A-ring 7, and then deprotection of the hydroxyl functions.     

Synthesis of 14-epi-19-nor-22-oxa-1α,25-dihydroxyvitamin D3

The synthesis of 14-epi-19-nor-22-oxa-1α,25（OH）2D3 5 was started from diol 8 via Fall＇s method, oxidation, epimerization, protection, coupling with the 19-nor-A-ring 7, and then deprotection of the hydroxyl functions.     

A Novel Synthesis of β-Hydroxy-α-amino Acids

β-hydroxy-α-amino acids constitute an important class of compounds as naturally occurring amino acids and as components of many complex natural products possessing a wide range of biological activities. [1] As a consequence of the essential role played by these amino acids in the biological systems and their utility as synthetic building blocks, a number of useful strategies have been devised for their preparation. [2]     

Novel Synthesis of Barbiturates

Knovenagel reaction of barbituric acid with different aldehydes were used to synthesize new barbiturates. This is a novel method which can be used to synthsis various types of new generation of barbiturates which are different from the previously reported.     

Novel Synthesis of 22,25-Dideoxyecdysone and Its 5α-Isomer

22,25-Dideoxyecdysone (1) and 5-22,25-dideoxyecdysone (1a) were prepared from cholesterol via a new scheme using the key intermediates 3-chloro-5-bromo-6-ketone 3, 3-chloro-7-bromo-6-ketone 4, and 2,7-dien-6-one 7.     

A Novel Synthesis of （-）-10-epi-a-Cyperone

An alternative route for the synthesis of (-)-10-epi-ct-cyperone 1 starting from ( )-dihydrocarvone 2 is described by using an asymmetric Michael addition as a key step. The routefeatures more efficiently and can be performed in large scale.     

Synthesis of Novel Polypyridine Ligands

IntroductionProject59333072supportedbyNSFC.TheaPPearAnceoftheruthenium(II)POlyPyridinecomplexeshasproducedanex1ensivegrowthinphotochendopandphotophysicsinlasttWentyyears,largelybecauseoftheirhighlyverboleltalnescentandphotoredoxproperties.Thesecomplexeshaveplayedandarestillplaytngven-imPOrtanroleinthedevelopmentofphotocherniStry,photophysics,photOCatalysis,eleetrchendap',photoelectrochendsto'chem-andelectrochend-lthenescence,andelectronandenergr'tr~fer1'3.ESPeCially,inarecentbreaktIir…     

Synthesis of Novel Nα, Nγ-Lysine Linked Dinucleotides

Reaction of O-nucleosid-5′-yl (or 3′-yl) O-alkyl H-phosphonate diesters with L-lysine methyl ester dihydrochlorides in the presence of Et₃N and CCl₄ produced the corresponding N^α, N^γ- lysine linked 5′, 5′(or 3′, 3′)-dinucleotides in excellent yield.     

Synthesis of Novel Isoxazole-contained Analogues of Losartan

Losartan 1 (Dup-753) is a nonpeptide angiotensin II receptor (type AT1) antagonist discovered by Duncia, J.V. et al. 1 in 1990 and its potassium salt (cozaar) has been marketed as an antihypertensive since 1995 2. 1 2 Starting from Dup-753, a great number of structural related compounds have been prepared by several laboratories and several antihypertensive drugs have been developed3. In order to find new and more active compounds, a novel type of Losartan analogues 2 was designed and syn…     

A Novel Synthesis of Difloxacin Hydrochloride

Difloxacin, the third generation of new quinolone antibiotics, has broad-spectrum in vitro activity and excellent potency in vivo and has been found to be against gram-positive cocci, gram-negative bacteria, anaerobe, mycoplasm, chlamydia1,2. As described previously, high reaction temperature and hazardous reagents are the defects of the methods for preparation of difloxacin3,4. We have developed a new synthetic method as shown in the Scheme. 2,4-Dichloro-5-fluoro-acetophenone 1 was used as …     

Synthesis of Novel Ferrocenyl-containing Thiazole Derivatives

Ferrocenes and their derivatives have been used in material chemistry, electrochemistry and in nonlinear optics. Recently, increasing interests have been focused on their biological activity1. Ferrocifen is a ferrocene derivative of tamoxifen, will be sub…     

The Synthesis of a Novel Lignan

Lignans have attracted much interest over the years on account of their widespread ocurrence in nature1, and on account of their broad range of biological activity2. Thus, several lignans are known to exhibit anti-tumor activity3-7, while others function as growth inhibitors and antifungal agents8,9. The importance is the isolation of lignans from animals, including human beings10-12, which has led to the suggestion that such compounds may be an example of a novel class of hormone controlling …     

Synthesis of Novel Antifungal Triazole Compounds

Based on our previous studies of 3D-QSAR, 38 novel objective compounds belonging to 4 series were designed and successfully synthesized directed by the idea of reconstructing the structure of non-pharmacophores while reserving essential ones in triazoles. In vitro pilot studies on their antifungal activities showed that most compounds have inhibitory effects on C.albicans and some inhibit S.cerevisiae also. The effects on C.albicans of 5 compounds are more potent than or equal to that of fluconazole or itraconazole.     

Synthesis of Some Novel γ-Spirolactones

Summary. We report on the addition of dialkyl acetylenedicarboxylate to 1-alkylisatins or tryptanthrine in the presence of triphenylphosphine which leads to highly functionalised novel unsaturated -spirolactones.     

A Novel Synthesis of Isoxazole Derivatives

Thenitronesareveryimportantinorganicsynthesis.TheyhavebeenwidelyutilizedasintermediatesfromwhichcomPlexheterocyclicornaturalcompoundsanddrugs"'weresynthesisedsuchasisoxazoline3andoxazine4.However,theconversionofnitronetoisoxazolebythermaldecompositionhasnotbeenreported.Inthispaper,wedevelopanewsyntheticmethodofisoxazolesfromheterocyclicnitronesasfollows:wi.-"'rtXfa.H;b.3,4-O-CH2-o-;c.4-CH3O,d.4-Cl;e.2-Brf.2-Cl,g.3,4-coCH3;h.3-ro2;i.4-so2;j.4-CH3Experiment8lAdriedroundbottomflaskundernit…     

A Facile Synthesis of 3-Oxo-7αH-eudesma-4-ene-9β, 12-diol

3-Oxo-7αH-eudesma-4-en-9β,12-diol1awasfirstisolatedfromCassinauncatabyKingetal.,anditsstructurewasdeterminedbyhighfieldNMRtechniques;however,theabsoluteconfigurationofC-llremainedunsolved.RecentlyPedroetalreportedthefirsttotalsynthesisof(llS)-3-oxo-7aH-eudesma-4-en-95,l21bfromartemisin2inl3steps'.Herein,wereportafacileprocedureforsynthesisofC-llisomericdiolsandthestereochemistryofnaturaldiol.Oursyntheticrouteisshownasbelow:a)ref5,36%;b)Vilsmeierreagent.30%H202,CH2Cl2.-20"C,lh.62%,c)i.…     

Novel Synthesis of Benzotriazol-1-yl Methyl Selenides and Tellurides

Benzotriazole has played an important role as a synthetic auxiliary for preparative chemists1. It is also well known that organic selenides or tellurides are versatile intermediates in organic synthesis2. However, there are only few reports on the synthesis of the difunctionalized compounds containing both benzotriazolyl group and organoselenium or tellurium group3. Herein we wish to report a new and convenient synthesis of benzotriazol-1-yl methyl selenides and tellurides 4a-h.Selenium or tel…