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:
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:
1-α-halo-2,2-difluoro-2-deoxy-D-ribofuranose derivative of formula (I) having the 3-hydroxy group protected with a biphenylcarbonyl group is a solid which can be easily purified by a simple procedure such as recrystallization, and therefore, it can be advantageously used as an intermediate in the preparation of gemcitabine in a large scale. Further, the 1-α-halo-2,2-difluoro-2-deoxy-D-ribofuranose derivative of formula (I) can be prepared with high stereoselectivity using the compound of formula (V) as an intermediate.
摘要:
3R-carboxylate enantiomer derivative of formula (III) can be prepared easily and selectively by the method of the present invention, and a highly pure D-erythro-2,2-difluoro-2-deoxy-1-oxoribose derivative can be prepared efficiently from the compound of formula (III) as an intermediate.
摘要:
3R-carboxylate enantiomer derivative of formula (III) can be prepared easily and selectively by the method of the present invention, and a highly pure D-erythro-2,2-difluoro-2-deoxy-1-oxoribose derivative can be prepared efficiently from the compound of formula (III) as an intermediate.
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:
The present invention relates to a pharmaceutical composition for treating or preventing obesity, comprising novel crystalline sibutramine methanesulfonate hemihydrate of formula (I). The crystalline sibutramine methanesulfonate hemihydrate according to the present invention has a much higher solubility in water, and enhanced stability under a high humidity/temperature condition, as compared with sibutramine hydrochloride monohydrate
摘要:
The present invention relates to a novel, high-yield and low-cost method for preparing entecavir, [1-S-(1α,3α,4β)]-2-amino-1,9-dihydro-9-[4-hydroxy-3-(hydroxymethyl)-2-methylenecyclopentyl]-6H-purin-6-one, an antiviral agent, and novel intermediates used therein.
摘要:
The present invention relates to a novel, high-yield and low-cost method for preparing entecavir, [1-S-(1α,3α,4β)]-2-amino-1,9-dihydro-9-[4-hydroxy-3-(hydroxymethyl)-2-methylenecyclopentyl]-6H-purin-6-one, an antiviral agent, and novel intermediates used therein.
摘要:
The present invention relates to a method for preparing capecitabine and a method for preparing a β-anomer-rich trialkyl carbonate compound used therein, and a highly pure capecitabine can be efficiently prepared with a high yield by the method of the present invention using the β-anomer-rich trialkyl carbonate compound as an intermediate.