Abstract: A glyoxal-guanosine-group compound is prepared either by reacting glyoxal-guanine with any one of ribose-1-phosphate and 2-deoxyribose-1-phosphate in the presence of purine nucleoside phosphorylase, or by reacting glyoxal-guanine with any one selected from the group consisting of uridine, 2?-deoxyuridine and thymidine, together with phosphate ion, in the presence of purine nucleoside phosphorylase and pyrimidine nucleoside phosphorylase. The glyoxal-guanosine-group compound is then decomposed by alkali, whereby a guanosine-group compound consisting of guanosine and 2?-deoxyguanosine is prepared.

Abstract: A method of producing an N-alkoxycarbonylpiperidine derivative, comprising reacting an N-aralkylpiperidine derivative represented by the following general formula (1): wherein R1 represents an aralkyl group which may have a substituent, with a mesyl halide in the presence of a base, thereby obtaining a mesylated product represented by the following general formula (2): wherein R1 represents an aralkyl group which may have a substituent and Ms represents a mesyl group, and reacting the mesylated product with a dicarbonate represented by the following general formula (3): wherein R4 represents an alkyl group, in the presence of hydrogen and a catalyst containing palladium, thereby obtaining an N-alkoxycarbonylpiperidine derivative represented by the following general formula (4): wherein R4 represents an alkyl group and Ms represents a mesyl group.

Abstract: A glyoxal-guanosine-group compound is prepared either by reacting glyoxal-guanine with any one of ribose-1-phosphate and 2-deoxyribose-1-phosphate in the presence of purine nucleoside phosphorylase, or by reacting glyoxal-guanine with any one selected from the group consisting of uridine, 2′-deoxyuridine and thymidine, together with phosphate ion, in the presence of purine nucleoside phosphorylase and pyrimidine nucleoside phosphorylase. The glyoxal-guanosine-group compound is then decomposed by alkali, whereby a guanosine-group compound consisting of guanosine and 2′-deoxyguanosine is prepared.

Abstract: A glyoxal-guanosine-group compound is prepared either by reacting glyoxal-guanine with any one of ribose-1-phosphate and 2-deoxyribose-1-phosphate in the presence of purine nucleoside phosphorylase, or by reacting glyoxal-guanine with any one selected from the group consisting of uridine, 2′-deoxyuridine and thymidine, together with phosphate ion, in the presence of purine nucleoside phosphorylase and pyrimidine nucleoside phosphorylase. The glyoxal-guanosine-group compound is then decomposed by alkali, whereby a guanosine-group compound consisting of guanosine and 2′-deoxyguanosine is prepared.

Abstract: A glyoxal-guanosine-group compound is prepared either by reacting glyoxal-guanine with any one of ribose-1-phosphate and 2-deoxyribose-1-phosphate in the presence of purine nucleoside phosphorylase, or by reacting glyoxal-guanine with any one selected from the group consisting of uridine, 2′-deoxyuridine and thymidine, together with phosphate ion, in the presence of purine nucleoside phosphorylase and pyrimidine nucleoside phosphorylase. The glyoxal-guanosine-group compound is then decomposed by alkali, whereby a guanosine-group compound consisting of guanosine and 2′-deoxyguanosine is prepared.

Abstract: The present invention provides a method of preparing stably and at a high yield a purine nucleoside compound by utilizing an exchange reaction of a nucleic acid base which is carried out in the presence of an enzyme, and also provides a microorganism capable of producing uracil thymine dehydrogenase or dihydrouracil dehydrogenase. In preparing the purine nucleoside compound, a pyrimidine nucleoside compound and a purine base are subjected to a base exchange reaction in an aqueous solution containing phosphate ions in the presence of pyrimidine nucleoside phosphorylase and purine nucleoside phosphorylase. The pyrimidine base formed by the base exchange reaction is converted by a microorganism or an enzyme derived from the microorganism into a compound incapable of acting as substrates of pyrimidine nucleoside phosphorylase and purine nucleoside phosphorylase so as to obtain a desired product of purine nucleoside compound.

Abstract: The instant invention provides a process for the industrial preparation of cis-hexahydroisoindoline derivatives in high yields and stereoselective manner. The instant invention relates to a process for the preparation of cis-hexahydroisoindoline derivative of formula II ##STR1## wherein R.sup.2 is hydrogen, alkyl, benzyl, acyl or alkoxycarbonyl, by catalytic reduction of isoindoline derivative of formula I ##STR2## wherein R.sup.1 is hydrogen, alkyl, benzyl, acyl or alkoxycarbonyl, wherein the catalytic reduction is carried out in the presence of a ruthenium, a rhodium or a palladium catalyst.

Abstract: A method of purifying 1,3-bis(3-aminopropyl)-1,1,3,3-tetraorganodisiloxane represented by the formula (I) as described hereinbefore, which comprises recrystallizing a crude product of the compound as its acid addition salt, and then neutralizing the acid addition salt to obtain a purified product of the compound. According to the method of the present invention, the compound of the formula (I) can be purified at high purity in high yield, and the purification treatment can be industrially conducted.

Abstract: The instant invention is drawn to a method for manufacturing 2',3'-dideoxy-2',3'-didehydronucleoside compounds by reacting a ribonucleoside derivative wherein the hydroxyl in the 5'-position of the furanose ring of said ribonucleoside is protected by a silyl protective group, with an acid anhydride such as acetic anhydride in the presence of a catalyst such as hydrous zirconium oxide, and then subjecting the reaction product to decarboxylation. The decarboxylation can be effected by heating the reaction product. This method can be performed in a single step, and requires no reagents which are expensive or chemicals which should be handled with care. Hence, it serves to manufacture 2',3'-dideoxy-2',3'-didehydronucleosides easily at low cost.

Abstract: 2'-deoxy-.beta.-adenosine can be industrially and easily obtained without using expensive or dangerous materials by the process of the present invention, which comprises the steps of: preparing a salt of adenine from adenine, allowing to condense the salt with a derivative of pentofuranose to isolate a derivative of adenine, and then eliminating the protecting groups.

Abstract: This invention provides a process for producing 3'-deoxy-'-fluorothymidine, which comprises allowing 3'-deoxy-'-fluoro-5'-mesylthymidine (the stating material) to react with an acetylating agent, selected from the group consisting of alkali metal salts of acetic acid, amine salts of acetic acid and ammonium acetate, in an aprotic, ploar solvent to form the 5'-acetyl derivative, and ammonium acetate, in an aprotic, polar solvent to form the 5'-acetyl derivative, and eliminating the 5'-acetyl group from this intermediate, thereby giving the objective 3'-deoxy-'-fluorothymidine.According to the process of this invention described above, the 5'-mesyl derivative can be efficiently acetylated, and 3'-deoxy-'-fluorotymidine can be obtained in a high yield.

Abstract: (S)-4-hydroxymethyl-.gamma.-lactone is prepared by oxidizing dihydrolevoglucosenone with a peracid in an organic solvent. (S)-4-hydroxymethyl-.gamma.-lactone is prepared from levoglucosenone. First, levoglucosenone is catalytic hydrogenated, thereby dihydrolevoglucosenone is obtained. Next, dihydrolevoglucosenone thus obtained is oxidized with a peracid in an organic solvent, thereby (S)-4-hydroxymethyl-.gamma.-lactone is obtained. In this manner, (S)-4-hydroxymethyl-.gamma.-lactone can be obtained with high optical purity.

Abstract: The present invention is a process for preparing 2'-deoxy-5-trifluoromethyl-.beta.uridine characterized in that a 5-trifluoromethyl-2,4-bis(triorganosilyloxy)pyrimidine and a 1-halogeno-2-deoxy-.alpha.-D-erythro-pentofuranose derivative are subjected to condensation reaction in chloroform to give a 1-(2-deoxy-.beta.-D-erythro-pentofuranoxyl)-5-trifluoromethyluracil derivative which is then subjected to the deprotection reaction to give 2'-deoxy-5-trifluoromethyl-.beta.-uridine.

Abstract: A method of preparing (S)-.gamma.-hydroxymethyl-.alpha.,.beta.-butenolide includes the step of oxidizing a levoglucosenone with a peracid in an organic solvent. Peracetic acid, metha-chloroperbenzoic acid or magnesium monoperoxyphthalate hexahydrate can be used as the peracid. According to this method, an (S)-.gamma.-hydroxymethyl-.alpha.,.beta.-butenolide having high optical purity can be easily prepared from a levoglucosenone as a starting material at a high yield.

Abstract: A 1,2,2-trimethyl-1-phenylpolydisilane is prepared by condensating 1,2-dichloro-1,2,2-trimethyl-1-phenyldisilane in the presence of an alkali metal or alkali earth metal, in an aprotic solvent. This polymer is a viscous liquid which has a weight average molecular weight in the range of from 5,000 to 500,000 and a narrow molecular weight distribution, and has various uses as electroconductors, photoresist and optical information recording materials.

Abstract: A dimethylphenysilylmethylpolysilane is prepared by condensating 1,1-dichloro-1,2,2-trimethyl-2-phenyldisilane in the presence of an alkali metal or alkali earth metal, in an aprotic solvent. This polymer is a viscous liquid which has a weight average molecular weight in the range of from 5,000 to 500,000 and a narrow molecular weight distribution, and has various uses as electroconductors, photoresist and optical information recording materials.

Abstract: This invention relates to 1,2-dichloro-1,2,2-trimethyl-1-phenyldisilane expressed by the chemical formula (II),Cl(CH.sub.3).sub.2 SiSi(CH.sub.3)(C.sub.6 H.sub.5)Cl.This invention further relates to a method for producing 1,2-dichloro-1,2,2-trimethyl-1-phenyldisilane by reacting phenyl lithium with 1,1,2-trichloro-1,2,2-trimethyldisilane expressed by the chemical formula (III),Cl(CH.sub.3).sub.2 SiSi(CH.sub.3)Cl.sub.2.This invention still further relates to a method for producing 1,2-dichloro-1,2,2-trimethyl-1-phenyldisilane by reacting 1,1,2-trichloro-1,2,2-trimethyldisilane with phenylmagnesium halide expressed by the general formula (IV), C.sub.6 H.sub.5 MgX (X=halogen atom) in the presence of a cobalt catalyst.

Abstract: This invention relates to a novel asymmetric 1,1-dichloro-1,2,2-trimethyl-2-phenyldisilane expressed by the chemical formula (I), (C.sub.6 H.sub.5) (CH.sub.3).sub.2 SiSi(CH.sub.3)Cl.sub.2.This invention further relates to a method for producing 1,1-dichloro-1,2,2-trimethyl-2-phenyl disilane by reacting 1,1,2-trichloro-1,2,2-trimethyl disilane expressed by the chemical formula (III), Cl(CH.sub.3).sub.2 SiSi(CH.sub.3)Cl.sub.2 with phenyl magnesium halide expressed by the general formula (IV), C.sub.6 H.sub.5 MgX (X=halogen atom) in the presence of a transition metal (except for cobalt) catalyst.