137568-30-0Relevant articles and documents
Bio-based poly(hexamethylene terephthalate) copolyesters containing cyclic acetalized tartrate units
Japu, Cristina,De Ilarduya, Antxon Martínez,Alla, Abdelilah,Mu?oz-Guerra, Sebastián
, p. 1573 - 1582 (2013)
A cyclic acetal of dimethyl l-tartrate (dimethyl 2,3-di-O-methylene l-threarate, Thx) was used as comonomer of dimethyl terephthalate (DMT) in the polycondensation with 1,6-hexanediol (HD) in the melt. Random copolyesters PHTxThxy with contents in tartrate units up to 50% were obtained with satisfactory molecular weights (Mw between 20,000 and 50,000) and dispersities slightly above 2, and without apparent discoloration. The copolyesters started to decompose above 300 °C. The Tg of the copolyesters oscillated between +9 and -9 °C with values steadily decreasing with increasing contents in Thx units. All the copolyesters as well as the homopolyester entirely made of tartrate units were semicrystalline with Tm falling from ～145 °C for PHT to ～70 °C for PHThx with intermediate values decreasing as the content in Thx increased. Copolyesters containing up to 30% of tartrate units were able to crystallize from the melt at crystallization rates that were delayed by the presence of tartrate units. The PHT70Thx30 copolyester displayed significant hydrodegradability when incubated in aqueous buffer and also certain biodegradability when subjected to the action of porcine pancreas lipases.
A Novel Synthesis of Optically Active C2-Symmetric Pyridine Derivatives. Efficient Reaction of Chiral Triflates with 2-Picolyllithium Reagents.
Kotsuki, Hiyoshizo,Nakagawa, Yuichi,Moriya, Narimasa,Tateishi, Hirotaka,Ochi, Masamitsu,et al.
, p. 1165 - 1174 (1995)
A variety of optically active C2-symmetric pyridine derivatives have been prepared from L- or D-tartaric acid as a chiral source via efficient coupling reactions of triflates with 2-picolyllithium reagents, and the utility of 17 and 18 as chiral ligands in the catalytic enantioselective addition of diethylzinc to benzaldehyde has been demonstrated (up to 41percent ee).The synthetic procedure for the corresponding meso-isomer was also described.
Catalytic enantioselective dibromination of allylic alcohols
Hu, Dennis X.,Shibuya, Grant M.,Burns, Noah Z.
supporting information, p. 12960 - 12963 (2013/09/24)
A new dibromination reaction involving the combination of dibromomalonate as the bromonium source and a titanium bromide species as the bromide source has been developed. Enantioselective catalysis has been achieved through apparent ligand acceleration by a tartaric acid-derived diol.
ASYMMETRIC SYNTHESIS OF ROCAGLAMIDES VIA ENANTIOSELECTIVE PHOTOCYCLOADDITION MEDIATED BY CHIRAL BRONSTED ACIDS
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Page/Page column 40-41, (2008/06/13)
The present invention provides a new strategies for the synthesis of compounds of the rocaglamide family and related natural products. The synthetic approach generally involves photochemical generation of an oxidopyrylium species from a 3-hydroxychromone derivative followed by an enantioselective 1,3-dipolar cycloaddition of the oxidopyrylium species to a dipolarophile in the presence of a TADDOL derivative. This approach can be used for the formation of adducts containing an aglain core structure. Methods of the conversion of aglain core structures to aglain, rocaglamide and forbaglin ring systems are also provided. The present invention also relates to the use of rocaglamide/aglain/forbaglin derivatives for the manufacture of medicaments for use in the treatment of cancer or cancerous conditions, disorders associated with cellular hyperproliferation, or NF-κB-dependent conditions.
