N,N'-Di-Boc-1H-pyrazole-1-carb

Solid-Phase Guanidinylation of Peptidyl Amines Compatible with Standard Fmoc-Chemistry: Formation of Monosubstituted Guanidines

-pyrazole-1-carboxamidine and triflylguanidine, and guanidinylation with di-protected thiourea derivatives in combination with promoters such as Mukaiyama’s reagent, N -iodosuccinimide, and N ,N′ -diisopropylcarbodiimide.

环肽的合成方法

反应。几乎所有可用于偶联反应的活泼酯都可用于合成环肽，主要有对硝基酚酯、N-羟基琥珀酰亚胺酯、五氟苯酯和2，4，5-三氯苯酚酯。线性多肽的C端羧基与对硝基酚、N-羟基琥珀酰亚胺、五氟苯酚或2，4，5-三氯苯酚，在DCC或其他缩合剂存在下，于低温反应，很容易得到相应的活泼酯。这种N端通常带有BOC或Z保护的活泼酯在酸性条件下脱去保护基，形成活泼酯的氢卤酸盐，在弱碱性稀溶液中，如在吡啶，DMF或二氧六环一类介电常数较大的溶剂中，保持pH8～9，加热（60～100℃）或室温搅拌数小时至数日，最终可得到环肽

Biotinylation of a Propargylated Cyclic (3′‐5′) Diguanylic Acid and of Its Mono‐6‐Thioated Analog Under “Click” Conditions

?butyldimethylsilyl?3??O ?[(2?cyanoethyl)?N ,N ?diisopropylaminophosphinyl]guanosine. The reaction product is then converted to the mono?6?thioated c?di? GMP biotinylated conjugate under conditions highly similar to those described above for the preparation