摘要:
This invention relates to an improved method for stereoselectively preparing 2¢¥-deoxy-2¢¥,2¢¥-difluorocytidine of formula (I), which comprises the steps of reacting a 1-halo ribofuranose compound of formula (III) with a nucleobase of formula (IV) in a solvent to obtain a nucleoside of formula (II) with removing the silyl halide of formula (V) produced during the reaction; and deprotecting the nucleoside of formula (II) to obtain 2¢¥-deoxy-2¢¥,2¢¥-difluorocytidine of formula (I).
摘要:
Provided is an improved method for stereoselectively preparing 2′-deoxy-2′,2′-difluorocytidine of formula (I), which includes reacting a 1-halo ribofuranose compound with a nucleobase of formula (IV) in a solvent to obtain a nucleo side of formula (II) with removal of a silyl halide ((alkyl)3SiX (X=halide)); and deprotecting the nucleoside of formula (II) to obtain 2′-deoxy-2′,2′-difluorocytidine of formula (I). 2′-Deoxy-2′,2′-difluorocytidine of formula (I) is effective for treating various cancers such as non-small cell lung (NSCLC), pancreatic, bladder, breast or ovarian cancers.
摘要:
Disclosed is (S)-(−)-amlodipine camsylate or a hydrate thereof having good photostability and high solubility, and a pharmaceutical composition comprising same, which can be efficiently used in treating cardiovascular diseases.
摘要:
There is provided a method for fabricating a ferroelectric memory device, which can prevent the deterioration of the ferroelectric characteristics from etching damage generated during etching process of the interlayer-insulating layer formed over the capacitor to form a contact hole. The present invention is characterized by etching the interlayer-insulating layer with the use of time-modulated plasma, namely pulsed-power plasma. Accordingly, the present invention can prevent the deterioration of the ferroelectric characteristics from etching, omit or reduce the later separate thermal process for recovering the etching damage and enhance the reliability of device.