A compound represented by general formula (I) wherein all the symbols are as defined in the specification has a selective S1P5 receptor agonist activity due to having a linker from a phenyl group to a cyclic substituent in a dihydronaphthalene skeleton; i.e., due to having a short linker of one atom or less as L in general formula (I), and can therefore serve as an agent for treating S1P5-mediated disease, e. g., neurodegenerative disease such as schizophrenia. ##STR00001##

A compound represented by general formula (I) wherein all the symbols are as defined in the specification has a selective S1P5 receptor agonist activity due to having a linker from a phenyl group to a cyclic substituent in a dihydronaphthalene skeleton; i.e., due to having a short linker of one atom or less as L in general formula (I), and can therefore serve as an agent for treating S1P5-mediated disease, e. g., neurodegenerative disease such as schizophrenia. ##STR00001##

Methods of preparing unsaturated compounds or analogs through dehydrogenation of corresponding saturated compounds and/or hydrogenation of aromatic compounds are disclosed.

Methods of preparing unsaturated compounds or analogs through dehydrogenation of corresponding saturated compounds and/or hydrogenation of aromatic compounds are disclosed.

A compound represented by general formula (I)

##STR00001##

(wherein, all the symbols are as defined in the specification) has a selective S1P.sub.5 receptor agonist activity due to having a linker from a phenyl group to a cyclic substituent in a dihydronaphthalene skeleton; .i.e., due to having a short linker of one atom or less as L in general formula (I), and can therefore serve as an agent for treating S1P.sub.5-mediated disease, e.g., neurodegenerative disease such as schizophrenia.

A compound represented by general formula (I)

##STR00001##

(wherein, all the symbols are as defined in the specification) has a selective S1P.sub.5 receptor agonist activity due to having a linker from a phenyl group to a cyclic substituent in a dihydronaphthalene skeleton; .i.e., due to having a short linker of one atom or less as L in general formula (I), and can therefore serve as an agent for treating S1P.sub.5-mediated disease, e.g., neurodegenerative disease such as schizophrenia.

A method for converting cedarwood oil into high density fuels including, hydrogenating cedarwood oil in the presence of at least one hydrogenation catalyst to generate hydrogenated cedarwood oil, removing the hydrogenation catalyst from the hydrogenated cedarwood oil, purifying the hydrogenated cedarwood oil to produce a first high density fuel, isomerizing the first high density fuel in the presence of at least one acid catalyst catalyst to generate a hydrocarbon mixture including adamantanes, and distilling the adamantane mixture to produce a second alkyl-adamantane high density fuel.

A method for converting cedarwood oil into high density fuels including, hydrogenating cedarwood oil in the presence of at least one hydrogenation catalyst to generate hydrogenated cedarwood oil, removing the hydrogenation catalyst from the hydrogenated cedarwood oil, purifying the hydrogenated cedarwood oil to produce a first high density fuel, isomerizing the first high density fuel in the presence of at least one acid catalyst catalyst to generate a hydrocarbon mixture including adamantanes, and distilling the adamantane mixture to produce a second alkyl-adamantane high density fuel.

A method for producing an organometallic nucleophile includes reacting an organohalide and a metal or metal compound with each other by a mechanochemical process in the presence of an ether compound in an amount of 0.5 to 10.0 equivalents relative to 1 equivalent of the organohalide. By utilizing the method, a method for producing an organometallic nucleophile can be performed without using a large-scale apparatus, a reaction method for reactions between an organometallic nucleophile and various organic electrophiles can be performed by an efficient and simplified means, and a simplified method for producing an organometallic nucleophile can be performed with high reactivity.

A method for producing an organometallic nucleophile includes reacting an organohalide and a metal or metal compound with each other by a mechanochemical process in the presence of an ether compound in an amount of 0.5 to 10.0 equivalents relative to 1 equivalent of the organohalide. By utilizing the method, a method for producing an organometallic nucleophile can be performed without using a large-scale apparatus, a reaction method for reactions between an organometallic nucleophile and various organic electrophiles can be performed by an efficient and simplified means, and a simplified method for producing an organometallic nucleophile can be performed with high reactivity.