Kyowa Hakko Kogyo Co., Ltd.

Kyowa Hakko Kogyo Kabushiki Kaisha

Takayoshi Yamauchi

Kentaro Tamaki

Kaneaki Hattori

Shunichi Ikeda

Shun-ichi Ikeda

Kenji Nakao

Yoshimasa Miyazaki

Shigeru Matsumura

Morio Harada

Hisatoshi Shimizu

Novel cyclopentane derivatives which are useful as an intermediate for the preparation of N-(L-aspartyl)-N'-(2,2,5,5-tetramethylcyclopentanecarbonyl)-R-1,1-diaminoe thane are represented by the formula (I) ##STR1## wherein R.sub.1 is hydrogen and R.sub.2 is cyano, formyl, carbamoyl, alkanesulfonyloxy, or ##STR2## wherein R.sub.3 and R.sub.4 are the same or different and represent alkyl, substituted alkyl or R.sub.1 and R.sub.2 are combined to be methylsulfinylmethylene, acetoxymethylthiomethylene, halomethylthiomethylene, methylthiomethylene, alkoxymethylene, or --CH.sub.2 --O--.

Cyclopentane derivatives

Novel cyclopentane derivatives which are useful as an intermediate for the preparation of N-(L-aspartyl)-N'-(2,2,5,5-tetramethylcyclopetanecarbonyl)-R-1,1-diaminoet hane are represented by the formula (I) ##STR1## wherein R.sub.1 is hydrogen and R.sub.2 is cyano, formyl, carbamoyl, alkanesulfonyloxy, or ##STR2## wherein R.sub.3 and R.sub.4 are the same or different and represent alkyl, substituted alkyl or R.sub.1 and R.sub.2 are combined to be methylsulfinylmethylene, acetoxymethylthiomethylene, halomethylthiomethylene, methylthiomethylene, alkoxymethylene, or --CH.sub.2 --O--.

Novel cyclopentane derivatives which are useful as an intermediate for the preparation of N-(L-aspartyl)-N'-(2,2,5,5-tetramethylcyclopentanecarbonyl)-R-1,1-diaminoe thane are represented by the formula (I) ##STR1## wherein R.sub.1 is hydrogen and R.sub.2 is cyano, formyl, carbamoyl, alkanesulfonyloxy, or ##STR2## wherein R.sub.3 and R.sub.4 are the same or different and represent alkyl, substituted alkyl or R.sub.1 and R.sub.2 are combined to be methylsulfinylmethylene, acetoxymethylthiomethylene, halomethylthiomethylene, methylthiomethylene, alkoxy-methylene, or --CH.sub.2 --O--.

Compounds having anti-inflammatory and analgesic activity of the formula ##STR1## are produced from compounds having the formula ##STR2## by rearrangement in the presence of a base or an amide and (1) X S O X.sup.1 or X S O.sub.2 X.sup.1 where X and X.sup.1 are halogen or trifluoromethyl or (2) sulfur dioxide and halogen.

Process for producing an .alpha.-aromatic group substituted alkanoic

Permanent waving composition containing as active ingredients cysteine and N-acetylcysteine. The composition contains preferably 3-15% cysteine and 0.2-3% N-acetylcysteine. It is possible to avoid the separation of crystals derived from the air-oxidation of cysteine by the composition of the present invention.

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Sakai, Japan

Takayoshi Yamauchi