Hydrazide BODIPY

Hydrazide groups react with aldehyde and ketone groups to form hydrazone linkages (Chapter 2, Section 5.1). Three BODIPY derivatives are available that contain a hydrazine group modification of carboxylate side chains. Biomolecules such as proteins that don t normally possess aldehyde residues can be modified to contain them by a number of chemical means (Chapter 1, Section 4.4). 

BODIPY 530/550 C hydrazide is 4,4-difluoro-5,7-diphenyl-4-bora-3a,4a-diaza-s-indacene-3-propionyl hydrazide, a derivative of the basic BODIPY structure that contains two phenyl rings off the No. 5 and 7 carbon atoms and a propionic acid hydrazide group on the No. 3 carbon... 

Figure 9.31 The side-chain hydrazide group of this BODIPY derivative can be used to label aldehyde-containing molecules. Glycoconjugates may be labeled after oxidation of carbohydrates with sodium periodate to produce the required aldehydes.

BODIPY 530/550 C3 Hydrazide 4,4-difluoro-5,7-diphenyl-4-bora-3a,4a-diaza-s-indacene-3-propionyl hydrazide MW 430... 

The excitation maximum for BODIPY 530/550 C3 hydrazide occurs at 534nm and its emission at 551nm. The molecule has an extinction coefficient in methanol of about 79,OOOM cm-1 at 534nm. 

BODIPY 530/550 C3 hydrazide is insoluble in aqueous solution, but may be dissolved in DMF or methanol as a concentrated stock solution prior to addition of a small aliquot to a reaction. Coupling to aldehyde-containing molecules occurs rapidly with the formation of a hydrazone linkage. The reaction may be done in buffered environments having a pH range of 5-10. However, modification of glycoproteins with this fluorophore may not yield satisfactory... 

The excitation maximum for BODIPY 493/503 C3 hydrazide occurs at 498 nm and its emission at 506 nm. Since this is an extremely small Stoke s shift, it may be difficult to avoid completely problems of excitation-light scattering interference in critical emission measurements unless sub-optimal excitation wavelengths are used. The molecule has an extinction coefficient in methanol of about 92,000M-1cm 1 at 493 nm. 

Figure 9.33 Modification of aldehyde-containing molecules can be done through this BODIPY derivative s hydrazide group.

BODIPY 593/503 C3 hydrazide is 4,4-difluoro-l,3,5,7-tetramethyl-4-bora-3a,4a-diaza-s-indacene-8-propionyl hydrazide (Molecular Probes). Unlike BODIPY 530/550 C3 hydrazide, this BODIPY derivative contains substituents that shift to lower wavelengths the spectral characteristics of its fluorescent properties. The molecule is highly reactive toward aldehyde-containing compounds, including glycoproteins that have been oxidized with sodium periodate to create the requisite groups (Fig. 230). 

BODIPY 493/503 C3 hydrazide is insoluble in aqueous solution, but may be dissolved in DMF or DMSO as a concentrated stock solution prior to addition of a small... 

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