Mannich reaction, protein-formaldehyde

The functionalization reaction, which is particularly applied to collagen, is based on the aminomethylation of various substrates (see also Table 34, Chap. Ill) by employing the NH2 groups of the protein as Mannich amine reagents. Formaldehyde is preferred for crosslinking however, other agents, such as resols (see 432 in Chap. Ill,... 

A novel approach has been to allow serotonin to react with protein via the Mannich reaction. This is a simple reaction that enables one to use formaldehyde as a bridge between the amino groups of a protein and compounds containing one or more reactive hydrogens. The Mannich reaction has also been used to prepare reserpine conjugates. The antibody titers were not as satisfactory as those elicited by conjugates prepared by a p-carboxyazobenzene derivative linked to BSA by the mixed anhydride procedure. 

Fig. 10.3-6 Tyrosine modification using commercially available lysine-reactive probes, (a) The aliphatic amino group reacts chemoselectively with NHS esters, leaving the aniline amino group free to participate in the Mannich reaction. On addition of formaldehyde and a protein target, tyrosine residues are modified, (b) Modification of...

Fig. 10.3-5 Tyrosine modification using a when proteins are treated alone with either three component Mannich-type reaction. component, (b) The reaction conversion is (a) Aldehydes and anilines condense to listed for a number of anilines and aliphatic form imines in situ, which react with tyrosine amines using a-chymotrypsinogen A as the residues through an electrophilic aromatic substrate and formaldehyde as the aldehyde substitution reaction. No reaction occurs component.

---