Takasago International Corporation

Sansho Co., Ltd.

Toyohiko Kobayashi

Takashi Miura

Toshiyuki Murayama

Yoshifumi Yuasa

Akifumi Yoshida

Akira Sasaki

Yoshio Ishino

Mitsuhiro Yoshida

Akio Tachikawa

Masayoshi Kasai

Teruyoshi Akiyama

Hiroyuki Fujimori

Hiroyuki Kenmochi

Keiji Ohmori

Noriko Konita

To offer a method of producing useful para-menthane-3,8-diol having the excellent repellent action to harmful living things, including noxious insects, in high purity and high yield, simply, and economically by the use of citronellal as a raw material compound. The above-mentioned problems are resolved by the production method of this invention wherein citronellal is treated with aqueous sulfuric acid solution of 0.02 to 1.0 wt. % in concentration to produce para-menthane-3,8-diol. In case of recovering the produced para-menthane-3,8-diol, a method is preferably adopted, wherein after the reaction product is extracted with an aliphatic hydrocarbon solvent of 5 to 8 in carbon number, the extract is cooled down at temperature higher than the melting point of said aliphatic hydrocarbon solvent and of -10.degree. C. or less to crystallize para-menthane-3,8-diol.

Method for producing para-menthane-3,8-diol

A process for preferentially producing a 4-(1-carboxyalkyl) azetidin-2-one derivative represented by formula (II.beta.): ##STR1## wherein R.sup.3 represents a lower alkyl group and R.sup.4 represents a hydrogen atom or a hydroxy-protective group, which involves deesterifying and decarboxylating a 4-(1,1-dialkoxycarbonylalkyl) azetidin-2-one derivative represented by formula (I): ##STR2## wherein R.sup.1 and R.sup.2 are identical or different and each represents an alkyl group, an alkenyl group, or an aralkyl group, R.sup.3 and R.sup.4 each has the meaning as defined above, and R.sup.5 represents an amino-protective group, and after that, eliminating the amino-protective group from the derivative, where the 4-(1-carboxyalkyl)azetidin-2-one derivative of formula (II.beta.) is present in an amount of at least 61% by mol of all 4-(1-carboxyalkyl)azetidin-2-one derivatives produced.

4-(1,1-dialkoxycarbonylalkyl) azetidin-2-one derivative and process for

A 4-(1,1-dialkoxycarbonylalkyl )azetidin-2-one derivative represented by formula (I): ##STR1## wherein R.sup.1 and R.sup.2 are identical or different and each represents an alkyl group, an alkenyl group, or an aralkyl group, R.sup.3 represents a lower alkyl group, R.sup.4 represents a hydrogen atom or a hydroxyl-protective group, and R.sup.5 represents a hydrogen atom or an amino-protective group, and a process for producing a 4-(1-carboxyalkyl)azetidin-2-one derivative represented by formula (II) useful as an intermediate for 1.beta.-alkylcarbapenem-type antibacterials: ##STR2## wherein R.sup.3 represents a lower alkyl group and R.sup.4 represents a hydrogen atom or a hydroxyl-protective group, which comprises de-esterifying and decarboxylating the derivative represented by formula (I), and in the case where an amino-protective group is present in the derivative of formula (I), eliminating the protective group from the derivative, are disclosed.

4-(1,1-dialkoxycarbonylalkyl)azetidin-2-one derivative and process for

Preparation for endermism containing dopamine derivatives

A process for preparing (1'R,3S)-3-(1'-hydroxyethyl)-azetidin-2-one or a derivative thereof represented by formula (I): ##STR1## wherein R.sup.1 represents a hydrogen atom or a hydroxyl-protective group, is disclosed, comprising reacting (2S,3R)-2-aminomethyl-3-hydroxybutyric acid or a derivative thereof represented by formula (II): ##STR2## wherein R.sup.1 is as defined above, with a sulfenamide represented by formula (III): ##STR3## wherein R.sup.2 represents ##STR4## and R.sup.3 and R.sup.4 each represent a hydrogen atom or a cyclic or acyclic hydrocarbon group, provided that they do not simultaneously represent a hydrogen atom, or R.sup.3 and R.sup.4 are taken together with the adjacent nitrogen atom to form a heterocyclic group, and triphenylphosphine. The reaction yield is high, and the sulfenamide (III) used as a lactamization reagent is cheap and can be recovered after the reaction.

Process for preparing (1'R,3S)-3-(1'-hydroxyethyl)-azetidin-2-one and

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Tokyo, Japan

Toyohiko Kobayashi