4455-13-4Relevant articles and documents
Stereoselective Cyclopropanation of (-)-Levoglucosenone Derivatives Using Sulfonium and Sulfoxonium Ylides
Ledingham, Edward T.,Merritt, Christopher J.,Sumby, Christopher J.,Taylor, Michelle K.,Greatrex, Ben W.
, p. 2652 - 2662 (2017/06/13)
The synthesis of tri- and tetrasubstituted cyclopropanes from 3-aryl-substituted levoglucosenones (LGO) has been developed. In contrast to the unstabilised ylide dimethylsulfonium methylide which gives epoxides from LGO via 1,2-addition, we have found that the soft nucleophile dimethylsulfoxonium methylide affords cyclopropanes in moderate yields from LGO and in excellent yields and stereoselectivity with 3-aryl LGO derivatives. The use of 1,1,3,3-tetramethylguanidine as base in DMSO to generate the ylide provided the best yields and shortest reaction times. Ester stabilised sulfonium ylides could also be used to generate tetrasubstituted cyclopropane derivatives. One of the products was converted into a cyclopropyl lactone via Baeyer-Villiger oxidation to demonstrate the utility of applying cyclopropanation chemistry to LGO. Georg Thieme Verlag Stuttgart.New York.
3-Thiolated 2-azetidinones: Synthesis and in vitro antibacterial and antifungal activities
Zarei, Maaroof,Mohamadzadeh, Masoud
experimental part, p. 5832 - 5840 (2011/08/10)
A series of 3-thiolated β-lactams were synthesized by [2+2] ketene-imine cycloaddition reaction from S-substituted mercaptoacetic acids and Schiff bases. Then, some of the 3-methylthio β-lactams were converted to 3-(methylsulfinyl) β-lactams and 3-(methylsulfonyl) β-lactams using m-CPBA under different reaction conditions. All the compounds were characterized by spectral data and elemental analyses and were evaluated for their in vitro antibacterial and antifungal activities against pathogenic strains including Staphylococcus aureus (Methicillin resistant strain). The preliminary screening results indicated that some of these compounds demonstrated moderate to very good antibacterial and antifungal activities.
PROCESS FOR PRODUCING ESTER COMPOUND
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Page/Page column 15-16, (2010/12/31)
PROBLEM To provide an environmentally-friendly method for producing industrially an ester compound. SOLUTION The present invention is a method for producing an ester compound which comprises subjecting a carboxylic acid and an alcohol to dehydration-condensation reaction using an involatile acid catalyst and then removing the residual acid catalyst by bringing a weak basic substance into contact with the residual acid catalyst.