{'fraction_non_alphanumeric': 0.025284450063211124, 'fraction_numerical': 0.0, 'mean_word_length': 6.008849557522124, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Antimicrotubular effect of calvatic acid and of some related compounds

A structure–activity relationship has been established between calvatic acid and some related synthetic compounds, and their ability to inhibit GTP‐induced microtubular protein polymerization in vitro. These compounds were effective in a dose‐ and a time‐dependent manner. The most active drug was the p‐chloro substituted compound, which showed its inhibitory activity without any preincubation period, which the others needed. Since if cysteine was present, polymerization was no longer affected, an involvement of titratable –SH groups of tubulin could be suggested. In contrast, taxol‐induced polymerization was only slightly inhibited by these compounds, and colchicine‐binding activity was not generally impaired.