The present invention relates to a method of production of 4-boronophenylalanine (BPA) from 4-iodophenylalanine, in which all the functional groups of the amino acid are protected by benzyl protection method, and which uses isopropyl magnesium halogenide stabilized by a complexation base, and subsequent condensation of the resulting Grignard reagent with a boric acid ester. The final reaction step, catalytic hydrogenolysis or transfer hydrogenolysis of protecting groups on the amino acid, occurs after hydrolysis of the boronate ester groups.

Disclosed herein is a method of forming a compound of formula I:

##STR00001##

wherein the substituents are defined in the specification. In particular, the compounds of formula I can be converted to amino acids bearing quaternary stereocenters with exceptional optical purities.

Disclosed herein is a method of forming a compound of formula I:

##STR00001##

wherein the substituents are defined in the specification. In particular, the compounds of formula I can be converted to amino acids bearing quaternary stereocenters with exceptional optical purities.

The present invention relates to a method for the synthesis of cyclic depsipeptides, in particular emodepside, from the open form.

Disclosed herein are synthesis methods for coelenterazine. Also disclosed are articles including the coelenterazine and coelenterazine derivatives. Representative absorbent articles include disposable diapers and adult incontinence products.

Benzotriazole phenols with substituents either ortho to the phenol hydroxyl group and/or para to the phenol hydroxyl group can be prepared from the unsubstituted benzotriazole phenol by coupling reactions. The ortho substituent group can be a simple alkoxy or amino group, or the ortho substituent group can be a linking group, linking the benzotriazole phenol to another benzotriazole phenol group.

Benzotriazole phenols with substituents either ortho to the phenol hydroxyl group and/or para to the phenol hydroxyl group can be prepared from the unsubstituted benzotriazole phenol by coupling reactions. The ortho substituent group can be a simple alkoxy or amino group, or the ortho substituent group can be a linking group, linking the benzotriazole phenol to another benzotriazole phenol group.

An object of the present invention is to develop a protecting group, which can prevent solidification or insolubilization of a compound by protecting a functional group to achieve easy separation and purification after a reaction.

A diphenylmethane compound represented by general formula (1):

##STR00001## wherein Y represents OR.sup.19 (wherein R.sup.19 represents a hydrogen atom or an active ester-type protecting group), NHR.sup.20 (wherein R.sup.20 represents, for example, a hydrogen atom, a C.sub.1-6 linear or branched alkyl group, or an aralkyl group, at least one of R.sup.1 to R.sup.01 represents a group represented by formula (2):

OR.sup.11X-A(2) and the others each independently represent a hydrogen atom, a halogen atom, a C.sub.1-4 alkyl group, or a C.sub.1-4 alkoxy group; R.sup.11 represents a C.sub.1-16 linear or branched alkylene group; X represents O or CONR.sup.21 (wherein R.sup.21 represents a hydrogen atom, or a C.sub.1-4 alkyl group; and A represents, for example, a group represented by formula (3).

##STR00002##

An object of the present invention is to develop a protecting group, which can prevent solidification or insolubilization of a compound by protecting a functional group to achieve easy separation and purification after a reaction.

A diphenylmethane compound represented by general formula (1):

##STR00001## wherein Y represents OR.sup.19 (wherein R.sup.19 represents a hydrogen atom or an active ester-type protecting group), NHR.sup.20 (wherein R.sup.20 represents, for example, a hydrogen atom, a C.sub.1-6 linear or branched alkyl group, or an aralkyl group, at least one of R.sup.1 to R.sup.01 represents a group represented by formula (2):

OR.sup.11X-A(2) and the others each independently represent a hydrogen atom, a halogen atom, a C.sub.1-4 alkyl group, or a C.sub.1-4 alkoxy group; R.sup.11 represents a C.sub.1-16 linear or branched alkylene group; X represents O or CONR.sup.21 (wherein R.sup.21 represents a hydrogen atom, or a C.sub.1-4 alkyl group; and A represents, for example, a group represented by formula (3).

##STR00002##

Disclosed herein are synthesis methods for coelenterazine. Also disclosed are articles including the coelenterazine and coelenterazine derivatives. Representative absorbent articles include disposable diapers and adult incontinence products.