Synthesis and anti‐HIV activity of ­6‐amino‐6‐deoxy‐(1→3)‐β‐D‐curdlan sulfate

Abstract

6‐Amino‐6‐deoxy‐(1→3)‐β‐D‐curdlan sulfate was synthesized in three steps. First, curdlan was azidized by lithium azide (LiN3) and carbon tetrabromide (CBr4) with triphenylphosphine (Ph3P) in dimethylformamide (DMF). Second, the azido group was reduced to an amino group with sodium borohydride (NaBH4) in dimethyl sulfoxide (DMSO) to afford 6‐amino‐6‐deoxy‐(1→3)‐β‐D‐curdlan. Third, sulfation of the amino‐group‐containing curdlan with a sulfur trioxide‐pyridine complex produced a 6‐amino‐6‐deoxy‐(1→3)‐β‐D‐curdlan sufate exhibiting high anti‐HIV (human immunodeficiency virus) activity (EC50 = 0.912 µg/ml) and low cytotoxicity (CC50 = 2512 µg/ml). Copyright © 2003 John Wiley & Sons, Ltd.

Comparison of curdlan and its carboxymethylated derivative by means of Rheology, DSC, and AFM

“…Sulfation is a main method to realize or confer biological activity to polysaccharides, and inhibitory effects against HIV in vitro as well as structural studies on curdlan sulfate have been investigated extensively. [15][16][17] Carboxymethyl substitution is considered as another method to improve the functional properties for many polysaccharides. [18][19][20] In the case of curdlan, its carboxymethylated derivative has good water solubility as well as good bioactivity, and it has been added successfully to cosmetics due to its immunocompetence.…”

Click Chemistry on Curdlan: A Regioselective and Quantitative Approach to Develop Artificial β-1,3-Glucans with Various Functional Appendages

“…11 The subsequent azidation using sodium azide in DMSO (80 C, 36 h) afforded 6-azido-6-deoxy-curdlan (CUR-N 3 ). Quantitative and exclusive conversion of primary hydroxy-groups into azido-groups was confirmed by the 13 C NMR spectrum of the product, in which a peak assignable to hydroxymethyl-group (-CH 2 OH, 60.90 ppm) is entirely diminished and that of azidomethyl-group (-CH 2 N 3 , 50.72 ppm) newly appears (see Supporting Information).…”

‘Click chemistry’ on polysaccharides: a convenient, general, and monitorable approach to develop (1→3)-β-d-glucans with various functional appendages

“…18 Subsequent azidation using sodium azide in Me 2 SO (80°C, 36 h) afforded 6-azido-6-deoxycurdlan (1-N 3 ). Quantitative and exclusive conversion of primary hydroxyl groups into azido groups was confirmed by the 13 C NMR spectrum of the product (Fig.…”