{'fraction_non_alphanumeric': 0.028421052631578948, 'fraction_numerical': 0.024210526315789474, 'mean_word_length': 5.604166666666667, '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}}
Benzimidazoles as NMDA Glycine‐Site Antagonists: Study on the Structural Requirements in 2‐Position of the Ligand

A series of different substituted benzimidazole derivatives has been synthesized and evaluated for the ability to displace [ 3 H]MDL‐105,519 to rat cortical membranes. Two benzimid‐azole‐ 2‐carboxylic acids 9 b and 9 c, in this substitution pattern not yet described as glycine antagonists, showed IC50 values of 0.89 μM (9 b) and 38.0 μM (9 c). Replacement of the carboxylate function in 2‐position by a sulfonic acid moiety appreciably increased solubility, but decreased the affinity giving evidence for the strong need of the carboxylate group within the ligand. Further structure‐activity studies using benzimidazol‐2‐one derivatives with an acetic acid moiety adjacent to a ring nitrogen revealed new insights into the importance of amide functionalities within the heterocycle for the affinity of antagonist glycine‐site ligands