Sialic acid derivatives represented by the general formula (I): ##STR1## wherein R.sup.1 is a steroidal compound residue; R.sup.2 is H or alkyl; R.sup.3 is alkyl; ##STR2## wherein each of R.sup.6 and R.sup.7 is H, alkyl or the like and I is an integer of 0 to 6; or the like; X is O or S; R.sup.4 is H or acyl; and R.sup.5 is R.sup.14 O-- (R.sup.14 is H or acyl) or R.sup.15 NH--(R.sup.15 is acyl or the like); their salts, hydrates or solvates are provided. Sialic acid derivatives of the present invention are expected to be effective medicines for the prevention and therapy of senile dementia including Alzheimer's disease and the like, because they increase ChAT activity in cholinergic neurons.
本发明提供了一种以通式(I)表示的
唾液酸衍
生物:其中,R.sup.1是类
固醇化合物残基;R.sup.2是H或烷基;R.sup.3是烷基;其中,每个R.sup.6和R.sup.7是H、烷基或类似物,I是0到6的整数;或类似物;X是O或S;R.sup.4是H或酰基;R.sup.5是R.sup.14 O--(其中,R.sup.14是H或酰基)或R.sup.15 NH--(其中,R.sup.15是酰基或类似物);其盐、
水合物或溶剂化物也被提供。本发明的
唾液酸衍
生物预计可作为预防和治疗老年性痴呆症,包括阿尔茨海默病等的有效药物,因为它们可以增加
胆碱能神经元中的
乙酰胆碱酯酶活性。