Triazabutadienes as cleavable cross-linkers

A clickable triazabutadiene according to (a) Formula B wherein X1 comprises a terminal azide handle or a terminal alkyne handle;

• or (b) Formula C wherein either X1 comprises a terminal azide handle or a terminal alkyne handle, X1 comprises a terminal azide handle or a terminal alkyne handle, or both X1 and X comprise a terminal azide handle or a terminal alkyne handle;
• wherein A=S, O, or N;
• D=H, —CH═CH—CH=E-, halides, cyano, sulfonates, alkyl chain, or trifluoromethyl;
• E=H, —CH═CH—CH=D-, halides, cyano, sulfonates, alkyl chain, or trifluoromethyl;
• and wherein Y′ comprises a tri-substituted aryl group;
• wherein azide handles are adapted to cross-link to an alkyne handle of a linking component via click chemistry or alkyne handles are adapted to cross-link to an azide handle of a linking component via click chemistry.