Although heparan sulfate (HS) is widely implicated in numerous physiological and pathological processes, the biological function of nucleus HS remains underexplored, largely due to its complex structure and high hydrophilic property. To supplement these efforts, ideal vehicles are drawing attention as they combine attractive features including lipid solubility for penetrating cell membrane, high affinity binding to its target receptor, metabolic stability, and no cellular actions resulting in toxicity. Herein, we develop a convenient and promising strategy to prepare HS-FK506 conjugates for membrane transport and entry into nucleus, where click chemistry takes easily place between the exocyclic allyl group of a clinic drug FK506 and thiol as a handle incorporated into HS analogues. HS derivatives for constructing the conjugates were synthesized using a cutting-edge chemoenzymatic method. Meantime, [³⁵S] labeled 3′-phosphoadenosine 5′-phosphosulfate (PAP³⁵S) and [¹⁴C] glucuronic acid (Glc A) were adopted to label HS-FK506 conjugates, respectively, to evaluate their efficiency of nucleus entry, as a result, ¹⁴C Glc A was sensitive, effective and reliable whereas PAP³⁵S gave rise to a mixture of labeled compounds, hampering the understanding of structure-function relationship of nucleus HS. Compared with the corresponding HS, the amount of HS-FK506 conjugates to translocate into nucleus from radioactive assay experiments sharply increased, e.g. tridecasaccharide-FK506 1d increased by approximate 10 folds, offering a simple and robust platform for enabling hydrophilic compounds including carbohydrates to translocate into nucleus and shedding light on their biological functions.

尽管硫酸乙酰肝素（HS）广泛参与许多生理和病理过程，但由于其复杂的结构和高亲水性，HS核的生物学功能仍未得到充分研究。为了补充这些努力，理想的媒介物吸引了人们的注意，因为它们结合了吸引人的功能，包括渗透细胞膜的脂溶性，与目标受体的高亲和力结合，新陈代谢的稳定性以及没有导致毒性的细胞作用。在本文中，我们开发了一种方便且有前途的策略来制备用于膜运输和进入细胞核的HS-FK506偶联物，其中单击化学很容易在临床药物FK506的环外烯丙基和作为掺入HS类似物的硫醇之间发生。使用尖端的化学酶法合成用于构建缀合物的HS衍生物。与此同时， [^{结果，分别使用35} S]标记的3'-磷酸腺苷5'-磷酸硫酸盐（PAP ³⁵ S）和[ ¹⁴ C]葡萄糖醛酸（Glc A）标记HS-FK506缀合物，以评估其进入核的效率。 ，¹⁴ C Glc A是灵敏，有效和可靠的，而PAP ³⁵ S产生了标记化合物的混合物，这妨碍了对HS核结构与功能关系的理解。与相应的HS相比，通过放射性测定实验转位到核中的HS-FK506缀合物的数量急剧增加，例如十三糖FK506 1d 增加了大约10倍，提供了一个简单而强大的平台，使亲水性化合物（包括碳水化合物）能够转移到细胞核中，并减轻其生物学功能。