{'fraction_non_alphanumeric': 0.04036557501904037, 'fraction_numerical': 0.021325209444021324, 'mean_word_length': 4.972727272727273, '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}}
Conformational analysis of the glycosaminoglycans. II. Bond-angle studies, torsional potential, and steric map for the beta-D-(1leads to 3) linkage.

The geometry of the glycosidic valence-bond angle for both the beta-D-(1linked to4) and beta-D-(1linked to 3) linkages has been investigated by using CNDO and PCILO molecularorbital techniques on model compounds. In each case, the glycosidic valence-bond angle of minimum energy was about 111 degrees, corresponding to the value observed in ether analogs. A secondary energy-minimum was found near 116 degrees, which is the value experimentally observed for saccharides. It was concluded that long-range intra-and/or inter-molecular interactions are responsible for overall preference for the 116 degrees value of the valence-bond angle. The force constants predicted from the shapes of the 116 degrees bond-angle minima gave poor agreement with the experimental values found for ethers and employed in normal coordinate analyses of saccharides. The results did suggest that the beta-D-(1linked to3) bond angle should be 115.6 degrees, which is smaller than the corresponding beta-D-(1linked to4) bond angle. An intrinsic torsional potential-function and general steric map were also determined for the torsion-angle rotations of the beta-D-(1linked to3) linkage.