Open AccessAnti-HIV-1 Activity and Structure-Activity Relationship of Cepharanoline Derivatives in Chronically Infected Cells
Author(s) -
Masanori Baba,
Masato Okamoto,
Noriaki Kashiwaba,
Minoru Ôno
Publication year - 2001
Publication title -
antiviral chemistry and chemotherapy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.919
H-Index - 51
eISSN - 2040-2066
pISSN - 0956-3202
DOI - 10.1177/095632020101200506
Subject(s) - mechanism of action , pharmacology , cell culture , stereochemistry , biology , inducer , ic50 , phorbol , biological activity , in vitro , structure–activity relationship , chemistry , biochemistry , enzyme , gene , protein kinase c , genetics
Cepharanthine (12- O-methyl cepharanoline) is a plant alkaloid and has been shown to inhibit tumour necrosis factor-α- or phorbol 12-myristate 13-acetate-induced HIV-1 replication in the chronically infected promonocytic cell line, U1. Its mechanism of action is considered to be the inhibition of nuclear factor κB, a potent inducer of HIV-1 gene expression. In this study, we have synthesized 96 derivatives of cepharanoline, including cepharanthine, and examined their inhibitory effects on HIV-1 replication in U1 cells. Among the 12- O-alkyl derivatives, cepharanthine proved to be the most active, and the activity decreased as the length of the alkyl chain increased. All of the 12- O-acyl derivatives were totally inactive, while a few 12- O-carbamoyl derivatives displayed modest activity. Since 12- O-ethyl derivatives were found to be as active as cepharanthine against HIV-1 replication, we further synthesized various 12- O-ethyl derivatives of cepharanoline. Among the derivatives, five proved to be more active inhibitors than cepharanthine, and the most active compound was 12- O-ethylpiperazinyl cepharanoline. The 50% effective concentrations of this compound and cepharanthine were 0.0041 and 0.028 μg/ml (0.0060 and 0.046 μM), respectively.