The present invention relates to compounds of formula (I) as defined herein. The compounds are suitable for protection against ultraviolet (UV) radiation. Further, the present invention is concerned with compositions comprising at least one compound of formula (I).

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The present invention relates to compounds of formula (I) as defined herein. The compounds are suitable for protection against ultraviolet (UV) radiation. Further, the present invention is concerned with compositions comprising at least one compound of formula (I).

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Process for the preparation of syndiotactic 1,2-polybutadiene comprising polymerising 1,3-butadiene in the presence of a catalytic system comprising: at least one pyridyl iron complex having the general formula (I), in which: R.sub.1 represents a hydrogen atom; or a methyl group; R.sub.2 represents a hydrogen atom; or is selected from linear or branched C.sub.1-C.sub.10 alkyl groups; X, identical or different to one another, represent a halogen atom; or are selected from linear or branched, C.sub.1-C.sub.20 alkyl groups, OCOR.sub.3 groups or OR.sub.3 groups in which R.sub.3 is selected from linear or branched C.sub.1-C.sub.20 alkyl groups; n is 2 or 3; at least one aluminoxane having the general formula (II), (R.sub.4).sub.2-AI-O-[-AI(R.sub.5)O-].sub.m-AI-(R.sub.6).sub.2 (ll) in which R.sub.4, R.sub.5 and R.sub.6, identical or different to one another, represent a hydrogen atom, or a halogen atom; or are selected from linear or branched C.sub.1-C.sub.20 alkyl groups, cycloalkyi groups, aryl groups, said groups being optionally substituted with one or more silicon atoms or germanium; and m is an integer ranging from 0 to 1000; in which the molar ratio between the aluminium present in the aluminoxane having the general formula (II) and the iron present in the pyridyl iron complex having the general formula (I) is ranging from 5 to 20. ##STR00001##

Process for the preparation of syndiotactic 1,2-polybutadiene comprising polymerising 1,3-butadiene in the presence of a catalytic system comprising: at least one pyridyl iron complex having the general formula (I), in which: R.sub.1 represents a hydrogen atom; or a methyl group; R.sub.2 represents a hydrogen atom; or is selected from linear or branched C.sub.1-C.sub.10, preferably C.sub.1-C.sub.3, alkyl groups; X, identical or different to one another, represent a halogen atom such as, for example, chlorine, bromine, iodine; or are selected from linear or branched, C.sub.1-C.sub.20, preferably C.sub.1-C.sub.15, alkyl groups, OCOR.sub.3 groups or OR.sub.3 groups in which R.sub.3 is selected from linear or branched C.sub.1-C.sub.20, preferably C.sub.1-C.sub.15, alkyl groups; n is 2 or 3; at least one aluminoxane having the general formula (II), (R.sub.4).sub.2-AI-O-[-AI(R.sub.5)O-].sub.m-AI-(R.sub.6).sub.2 (ll) in which R.sub.4, R.sub.5 and R.sub.6, identical or different to one another, represent a hydrogen atom, or a halogen atom such as, for example, chlorine, bromine, iodine, fluorine; or are selected from linear or branched C.sub.1-C.sub.20 alkyl groups, cycloalkyi groups, aryl groups, said groups being optionally substituted with one or more silicon atoms or germanium; and m is an integer ranging from 0 to 1000; in which the molar ratio between the aluminium present in the aluminoxane having the general formula (II) and the iron present in the pyridyl iron complex having the general formula (I) is ranging from 5 to 20, preferably ranging from 8 to 12.

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The invention relates to inhibitors of Sphingosine Kinase enzymatic activity, and methods of treating diseases and disorders by administering inhibitors of Sphingosine Kinase enzymatic activity.

According to an embodiment of the present invention, there is provided a novel fluorene-based compound and a photopolymerization initiator using the fluorene-based compound. The fluorene-based compound according to an embodiment of the present invention is represented by the general formula (1). A photopolymerization initiator having additionally high sensitivity can be provided by using the fluorene-based compound. In addition, a photopolymerization initiator that can impart additionally excellent characteristics can be provided by appropriately selecting, for example, a substituent.

According to an embodiment of the present invention, there is provided a novel fluorene-based compound and a photopolymerization initiator using the fluorene-based compound. The fluorene-based compound according to an embodiment of the present invention is represented by the general formula (1). A photopolymerization initiator having additionally high sensitivity can be provided by using the fluorene-based compound. In addition, a photopolymerization initiator that can impart additionally excellent characteristics can be provided by appropriately selecting, for example, a substituent.