Methods and reagents for esterification of biological molecules including proteins, polypeptides and peptides. Diazo compounds of formula I: ##STR00001##
where R is hydrogen, an alkyl, an alkenyl or an alkynyl, R.sub.A represents 1-5 substituents on the indicated phenyl ring and R.sub.M is an organic group. R.sub.M includes a label, a cell penetrating group, a cell targeting group, or a reactive group or latent reactive group for reaction to bond to a label, a cell penetrating group, or a cell targeting group, among other organic groups useful for esterification of biological molecules. Also provided are diazo compounds which are bifunctional and trifunctional coupling reagents as well as reagents for the synthesis of compounds of formula I.

Methods and reagents for esterification of biological molecules including proteins, polypeptides and peptides. Diazo compounds of formula I: ##STR00001##
where R is hydrogen, an alkyl, an alkenyl or an alkynyl, R.sub.A represents 1-5 substituents on the indicated phenyl ring and R.sub.M is an organic group. R.sub.M includes a label, a cell penetrating group, a cell targeting group, or a reactive group or latent reactive group for reaction to bond to a label, a cell penetrating group, or a cell targeting group, among other organic groups useful for esterification of biological molecules. Also provided are diazo compounds which are bifunctional and trifunctional coupling reagents as well as reagents for the synthesis of compounds of formula I.

The present disclosure provides methods of preparing a compound of Formula (1): wherein R.sup.1, R.sup.2, and R.sup.3 are as defined as set forth in the application. In one embodiment, a compound of Formula (1) is prepared in >95% chemical purity and >95% enantiomeric excess.

##STR00001##

Methods and reagents for esterification of biological molecules including proteins, polypeptides and peptides. Diazo compounds of formula I:

##STR00001##

where R is hydrogen, an alkyl, an alkenyl or an alkynyl, R.sub.A represents 1-5 substituents on the indicated phenyl ring and R.sub.M is an organic group. R.sub.M includes a label, a cell penetrating group, a cell targeting group, or a reactive group or latent reactive group for reaction to bond to a label, a cell penetrating group, or a cell targeting group, among other organic groups useful for esterification of biological molecules. Also provided are diazo compounds which are bifunctional and trifunctional coupling reagents as well as reagents for the synthesis of compounds of formula I.

Methods and reagents for esterification of biological molecules including proteins, polypeptides and peptides. Diazo compounds of formula I:

##STR00001##

where R is hydrogen, an alkyl, an alkenyl or an alkynyl, R.sub.A represents 1-5 substituents on the indicated phenyl ring and R.sub.M is an organic group. R.sub.M includes a label, a cell penetrating group, a cell targeting group, or a reactive group or latent reactive group for reaction to bond to a label, a cell penetrating group, or a cell targeting group, among other organic groups useful for esterification of biological molecules. Also provided are diazo compounds which are bifunctional and trifunctional coupling reagents as well as reagents for the synthesis of compounds of formula I.

The disclosure provides compounds having formula (I):

##STR00001##

and the pharmaceutically acceptable salts thereof, wherein R.sub.1, R.sub.2, R.sub.2′, and X are as defined as set firth in the specification. Compounds having formula (I) are prodrugs that release glutamine analogs, e.g., 6-diazo-5-oxo-L-norleucine (DON). The disclosure also provides compounds having formula (I) for use in treating cancer.

The disclosure provides compounds having formula (I):

##STR00001##

and the pharmaceutically acceptable salts thereof, wherein R.sub.1, R.sub.2, R.sub.2′, and X are as defined as set firth in the specification. Compounds having formula (I) are prodrugs that release glutamine analogs, e.g., 6-diazo-5-oxo-L-norleucine (DON). The disclosure also provides compounds having formula (I) for use in treating cancer.

The invention relates to novel glutamine analogs, a composition containing the glutamine analogs and the use thereof.

The invention relates to novel glutamine analogs, a composition containing the glutamine analogs and the use thereof.

Provided are a novel N-transfer reagent and a method for preparing the same and its application. The N-transfer reagent is represented by the following Formula (I): ##STR00001## The various novel N-transfer reagents of the present invention can be quickly prepared by employing different nitrobenzene precursors. The N-transfer reagents can directly convert a variety of amino compounds into diazo compounds under mild conditions. Particularly, the N-transfer reagents can facilitate the synthesis of the diazo compounds. The application of synthesizing diazo compounds of the present invention can greatly decrease the difficulty in operation, increase the safety during experiments, reduce the cost of production and the environmental pollution, and enhance the industrial value of diazo compounds.