Maleimide function

The common synthetic route to bismaleimides or maleimide functionalized oligomers is the condensation of diamines or amino-terminated oligomers with maleic anhydride. Another possibiUty is the use of an AB-type monomer of the following general formula to build the polymaleimide, where X represents a functional group that can be employed in condensation reactions. 

Houseman BT, Gawalt ES, Mrksich M (2003) Maleimide-functionalized self-assembled monolayers for the preparation of peptide and carbohydrate biochips. Langmuir 19 1522-1531... 

The first two compounds discussed in this section are truly sulfhydryl-reactive, using the common iodoacetyl and maleimide functionalities, respectively. The third derivative, however, is not reactive directly with sulfhydryl groups, but contains a protected sulfhydryl which, after deprotection, can be used to react with other sulfhydryl-reactive crosslinkers. 

Maleimide-functionalized peptides react quantitatively with thiols and thus with di-fatty acid substituted thioglycerol, a fact which facilitates purification of the amphiphilic lipopeptide derivatives by simple precipitation as required for separation of the excess lipid building block (Scheme 16).t163 164 167l... 

In the first approach, a maleimide-functionalized polystyrene of 40 repeat units (P DI = 1.04) was covalently coupled to the sulfur atom of a reduced disulfide bridge on the surface of the lipase B from Candida antarctica (CALB) (Figure 6.11a) [33]. TEM studies of the reaction mixture in water/THF revealed well-defined enzyme fibers with a length of several micrometers. The fibers consisted of bundles of rods, of which the smallest had diameters between 25 and 30 nm. These diameters were in... 

As before, the homopolymer forming reaction involved the generation of an o-quinoidimethane from benzocyclobutene which in turn reacted with the double bond of a maleimide functionality on a second monomer to give chain extended AB material via a Diels-Alder pathway. The polymers prepared to date using this type of approach have been shown to have excellent thermal and mechanical properties and have been considered as potential candidates for use as matrix resins for advanced composites. This area has been investigated by the researchers at both the Air Force Wright Laboratories and the Dow Chemical Co. 

Attempts to elucidate the polymerization or copolymerization kinetics of ethynyl and maleimide-functionalized monomers have been undertaken via vibrational spectroscopy (137). The thermal polymerization of A-(3-ethynyl-phenyl) maleimide (the structure is given in Fig. 48) was studied via IR and Raman spectroscopy. This model compound is interesting because it carries maleimide and ethynyl groups attached to the same aromatic ring. Kinetic studies indicate that both the acetylene and maleimide group react at the same rate, which strongly suggests the formation of a copolymer rather than a mixture of homopolymers. 

The maleimide functionality has also been utilized as a modifying group to obtain polymers crosslinkable by free radical chemistry. Thus, hydroxy-terminated poly(oxy-2,6-dimethyl-1,4-phenylene) (164) was treated with p-maleimidobenzoyl chloride (165) to obtain resin (166 Scheme 81) (72FRP2122181). Resin (166) melted at 155 °C and could be coated on to... 

Scheme 17 Chemoselective Ligation of Thiopeptides to a Maleimide-Functionalized Template 981...

However, due to the aromatic ring adjacent to its maleimide functional group, MBS displays less stability toward maleimide ring opening than SMCC (see this chapter Section 1.3). Unlike SMCC, MBS is therefore not recommended for preparing freeze-dried, maleimide-activated proteins, since during the processing necessary to purify and stabilize the derivative much activity can be lost by hydrolysis. 

Non-polymerisable monofunctional antioxidants were subsequently used to avoid the problem of homopolymerisation of the antioxidant. For example, melt grafting of the two maleated antioxidants, BPM and APM, on PP was shown to lead to high grafting efficiencies (up to 75% in the former and >90% in the latter) which were attributed to the non-polymerisable nature of the maleate (maleimide) functions [57, 59, 60]. The performance of these antioxidants, especially under extractive organic solvent conditions, was also shown to far exceed that of conventional antioxidants with similar antioxidant functions. Table 2, for example, shows the advantages of the grafted... 

Covalently immobilized arrays are formatted by glycans with functionalized spacers that react with a complementary activated surface to form a covalent bond. Several different covalent interactions were reported to construct a specified glycan array. Amine chemistry and thiol chemistry are the two major methods to conjugate glycans to the reactive substrate in the array surface (Fig. 15.2). Thiol chemistry was first adapted by Injae Shin in 2002 to react with the maleimide functional group (Fig. 15.2a, b) [7,41 ]. Disulfide bond formation was then reported for the fabrication... 

MAD was derivatized with 1-thio- 3-D-galactopyranose to give N-[/w-[3-(trifluoromethyl) diazirin-3-yl] phenyl]-4-(-3-thio(-l-D-galactopyranosyl)-succinimidyl) butyramide (Figure 2). The parent molecule MAD provides a maleimide function, allowing the reaction with thiogalactopyranose. Both MAD and its derivative MAD-Gal contain the diazirine function that yields carbenes upon light activation at 350 nm. 

The morphinan 1 with a maleimide function attached to the N-phenethyl side chain was five times as potent as morphine as an agonist in mice by the D Amour Smith test/26 Mice pretreated with the compound at 2 mg/kg were less responsive to morphine given after the analgesia to the morphinan had disappeared, but unequivocal classification of the mode of antagonism was not possible. 

Synthesis of inositol phosphoglycans (IPGs) (71), analogues to second messengers of insulin, has been described. These derivatives contain the glucosamine (a 1-6) myo-inositol 1,2 cyclic phosphate motif and the thiol-terminated spacers for efficient coupling to maleimide functionalized solid phases or proteins. ... 

Covalent immobilization of chemically synthesized carbohydrates onto derivatized surfaces by Seeberger group, (a) Attachment of thiol containing carbohydrates to maleimide-functionalized glass slides (b) attachment of amine-terminated heparin oligosaccharides onto amine-reactive glass slides... 

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