Store › SiR-tetrazine 1mg Image 1 of 1 SiR-tetrazine 1mg $838.00 Quantity: Add To Cart Added! SiR-tetrazine is a clickable derivative of SiR. It reacts with BCN and TCO derivatives. SiR-tetrazine is a clickable derivative of SiR. It reacts with BCN and TCO derivatives.