Diels-Alder ligation

Keywords Click ligation Diels-Alder ligation Expressed protein Ugation GPI anchor MIC ligation Peptide synthesis Protein lipidation Rab Ras Rheb Sortase-mediated protein ligation... 

Diels- Alder ligation Protein with a C-terminal dienyl group Non-natural bond Rab7... 

Experimental protocol for Staudinger-Bertozzi, Cu(l)-catalyzed Huisgen alkyne-azide cycloaddition, and reverse-electron-demand Diels-Alder ligation to distinguish between pi, p2,and p5. 

Engelsma SB, Willems LI, van Paaschen CE, van Kasteren SI, van der Marel GA, Overkleeft HS, Filippov DV (2014) Acylazetine as a dienophile in bioorthogonal inverse electron-demand diels-alder ligation. Org Lett 16(10) 2744-2747. doi 10.1021/ol501049c... 

Figure 9.4. ToFSIMS image resulting from the photolithographic patterning of PEGs onto phenacyl sulfide functional silicon wafers via a hetero Diels-Alder ligation. The red areas correspond to fragments associated with PEG, i.e. Cflffi, Cfiffi and CHfD. ...

PRE 14] Preuss C.M., ZiegerM.M., Rodriguez-Emmenegger C. et al., Fusing Catechol-Driven Surface Anchoring with Rapid Hetero Diels-Alder Ligation , ACS Macro Letters, vol. 3, pp. 1169-1173, 2014. 

Fig. 4 Chemoselective ligation methods a maleimide linker, b silyl linker, c Diels-Alder ligation, d glyoxylyl linker, e diazobenzylidene linker, f Staudinger ligation, g Huisgen [3 + 2] cycloaddition, h hydrazide linker, i glycal immobilization...

Figure 17.3 Maleimide-modified glass slides (1) can be derivatized using two chemoselective ligation reactions to create biotin modifications. In the first step, alkyne-PEG4-cyclopentadiene linkers (2) are added to the maleimide groups using a Diels-Alder reaction. In the second reaction, an azido-PEG4-biotin compound (3) is reacted with the terminal alkyne on the slide using click chemistry to result in another cycloaddition product, a triazole ring.

In 2006 an alternative protein ligation was published employing the highly selective and fast Diels-Alder reaction to the synthesis of lipoproteins. This reaction has already been used for bioconjugation... 

Aza-3-benzyl-l,5-diphenylpentane ligated Ti(lV) complex 17 is quite effective for the asymmetric inverse-electron-demand Diels-Alder reaction of... 

Many DNAzymes catalyse RNA ligation reactions to yield linear, branched, and lariat-type reaction products. The ligation of DNA strands as well as the phosphorylation of DNA or RNA oligonucleotides was described. Some notable extensions beyond phosphodiester chemistry include a photoreversion reaction, a deglycosylation, porphyrin metalation, nucleopeptide bond formation, and finally a Diels-Alder reaction. This latter reaction is essentially the same studied by the Jaschke lab with RNA as a catalyst (as discussed below in more detail), and the information published to-date indicates that the catalytic proficiency of DNA and RNA enzymes for Diels-Alder reactions is very similar. 

A new electron acceptor, 6-alkylpyrrolo[3,4-4]pyridazine-5,7-dione (PPD) 10, was prepared by Ye and collaborators via an inverse electron demand Diels—Alder reaction (Scheme 6) (140L6386).The authors synthesized both furan- and thiophene-ligated 6-alkylpyrrolo[3,4-first step of this synthesis involved treatment of either 2-cyanofuran or 2-cyanothiophene with hydrazine and sulfur in ethanol, followed by addition of isoamyl nitrite to form the respective tetrazine.The 5-positions of either the furan rings or the thiophene rings were then bro-minated with N-bromosucciriiinide (NBS) in DMF at 100 After stirring... 

A copper enolate is also regarded as an intermediate in a hetero-Diels-Alder-like sequence between a ketone and an analog of Danishefsky s diene, modified at silicon ii.e., (0Et)3 in place of Mes Scheme 1-12)J A fluoride-initiated (tetrabutylammonium difluorotriphenylsilicate [TBAT]) cleavage of the starting silyl enol ether leads to a nonracemically ligated (with Walphos) copper enolate, which condenses and then closes to the observed dihydropyranones in modest ee s. Noteworthy in this scheme is generation of the quaternary center. 

Blackman ML, Royzen M, Fox JM (2008) Tetrazine ligation fast bioconjugation based on inverse-electron-demand Diels-Alder reactivity. J Am Chem Soc 130(41) 13518-13519. doi 10.1021/ ja8053805... 

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