A compound of Formula I: ##STR00001##
wherein: X.sup.1-X.sup.8 are each independently C or N, wherein two adjacent X.sup.1-X.sup.8 are carbon-fused to a structure of Formula II: ##STR00002## X.sup.9-X.sup.12 are each independently C or N; A.sup.1, A.sup.2, and A.sup.3 are each independently selected from the group consisting of O, S, Se, N, NR, CR, CRR′, SiR, SiRR′, GeR, and GeRR′, with at least one of A.sup.1 and A.sup.2 being N or NR; each occurrence of is independently a single bond or a double bond, wherein one occurrence of is a single bond and one occurrence of is a double bond; each of R.sup.A, R.sup.B, and R.sup.c independently represents zero, mono, or up to a maximum allowed substitution to its associated ring; each of occurrence R, R′, R.sup.A, R.sup.B, and R.sup.C is independently a hydrogen or a substituent selected from the group consisting of Formula III, Formula IV, Formula V, Formula VI, Formula VII, Formula VIII, Formula IX, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, boryl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof, with at least one of R, R′, R.sup.A, R.sup.B, and R.sup.C comprising a group of Formula III, Formula IV, Formula V, Formula VI, Formula VII, Formula VIII, or Formula IX: ##STR00003## ##STR00004## each occurrence of Y.sup.1, Y.sup.2, and Y.sup.3 is independently absent, O, S, Se, NR, CRR′, SiRR′, or GeRR′; each occurrence of Ar.sup.1, and Ar.sup.2 is independently an optionally substituted aryl group or an optionally substituted heteroaryl group, wherein Ar.sup.1 and Ar.sup.2 are optionally joined or fused together to form a ring; each occurrence of X.sup.13-X.sup.20 is independently C or N, with the proviso that at least one of X.sup.13-X.sup.20 is N; each occurrence of A.sup.4 is selected from the group consisting of O, S, Se, NR, CRR′, SiRR′, and GeRR′; each occurrence of R.sup.X independently represents zero, mono, or up to a maximum allowed substitution to its associated ring; each occurrence of R.sup.X is in

An organic electroluminescent element including a substrate, a pair of electrodes including an anode and a cathode, disposed on the substrate, and at least one organic layer including a light emitting layer, disposed between the electrodes, in which at least one kind of compound represented by the following general formula is contained in any layer of the at least one organic layer, is an organic electroluminescent element, in which the generation of dark spots during driving is inhibited: ##STR00001##

An organic electroluminescent element including a substrate, a pair of electrodes including an anode and a cathode, disposed on the substrate, and at least one organic layer including a light emitting layer, disposed between the electrodes, in which at least one kind of compound represented by the following general formula is contained in any layer of the at least one organic layer, is an organic electroluminescent element, in which the generation of dark spots during driving is inhibited: ##STR00001##

A preparation method of an intermediate compound of formula II ((1R,2S,3S,4S,5S,6R,11S,14S,17S,19R,21R,23S,25R,26R,27S,31R,34S)-25-[(2S)-2,3-dihydroxy]-2,5-dihydroxy-26-methoxy-19-methyl-13,20-dimethylene-24,35,36,37,38,39-hexaoxane[29.3.1.1.sup.3,6.1.sup.4,34.11.sup.1,14.1.sup.17,21.0.sup.23,27]nonatriacontan-8,29-dione) for eribulin mesylate is provided, including subjecting a compound of formula I to a reaction with an additive in the presence of tetra-n-butylammonium fluoride (TBAF). The additive is piperidine hydrochloride or pyridine hydrochloride, and a reaction formula is as follows: ##STR00001## The present invention aims to avoid the problem that a traditional synthetic route has a low yield.

A preparation method of an intermediate compound of formula II ((1R,2S,3S,4S,5S,6R,11S,14S,17S,19R,21R,23S,25R,26R,27S,31R,34S)-25-[(2S)-2,3-dihydroxy]-2,5-dihydroxy-26-methoxy-19-methyl-13,20-dimethylene-24,35,36,37,38,39-hexaoxane[29.3.1.1.sup.3,6.1.sup.4,34.11.sup.1,14.1.sup.17,21.0.sup.23,27]nonatriacontan-8,29-dione) for eribulin mesylate is provided, including subjecting a compound of formula I to a reaction with an additive in the presence of tetra-n-butylammonium fluoride (TBAF). The additive is piperidine hydrochloride or pyridine hydrochloride, and a reaction formula is as follows: ##STR00001## The present invention aims to avoid the problem that a traditional synthetic route has a low yield.

The present invention provides methods for the synthesis of ketones involving a Ni/Zr-mediated coupling reaction. The Ni/Zr-mediated ketolization reactions can be used in the synthesis of halichondrins (e.g., halichondrin A, B, C; homohalichondrin A, B, C; norhalichondrin A, B, C), and analogs thereof. Therefore, the present invention also provides synthetic methods useful for the synthesis of halichondrins, and analogs thereof. Also provided herein are compounds (i.e., intermediates) useful in the synthesis of halichondrins, and analogs thereof. In particular, the present invention provides methods and compounds useful in the synthesis of compound of Formula (H3-A). ##STR00001##

The present invention provides methods for the synthesis of ketones involving a Ni/Zr-mediated coupling reaction. The Ni/Zr-mediated ketolization reactions can be used in the synthesis of halichondrins (e.g., halichondrin A, B, C; homohalichondrin A, B, C; norhalichondrin A, B, C), and analogs thereof. Therefore, the present invention also provides synthetic methods useful for the synthesis of halichondrins, and analogs thereof. Also provided herein are compounds (i.e., intermediates) useful in the synthesis of halichondrins, and analogs thereof. In particular, the present invention provides methods and compounds useful in the synthesis of compound of Formula (H3-A). ##STR00001##

The invention provides methods utilizing Prins reaction in the preparation of compounds that may be useful as intermediates in the synthesis of halichondrin macrolides and analogs thereof. The invention also provides compounds that may be useful as intermediates in the synthesis of a halichondrin macrolides and methods for preparing the same.

The invention provides methods utilizing Prins reaction in the preparation of compounds that may be useful as intermediates in the synthesis of halichondrin macrolides and analogs thereof. The invention also provides compounds that may be useful as intermediates in the synthesis of a halichondrin macrolides and methods for preparing the same.

Use of ginkgolide A in the treatment of autism. Specifically, the present invention relates to use of ginkgolide A, a stereoisomer thereof, a crystal form thereof, a pharmaceutically acceptable salt thereof, a derivative thereof, an extract comprising ginkgolide A, or a combination thereof in the preparation of a pharmaceutical composition for the treatment of autism. The experiments have demonstrated that ginkgolide A can significantly alleviate the behavioral defects of autism, and ginkgolide A has the advantages of small dosage and high safety when treating autism, and is very suitable as a common medicine for the treatment of autism.