Provided are a novel ammonium (3R,5S)-3,5,6-trihydroxyhexanoate derivative represented by the following formula (I):
 wherein R1 represents a benzyl group which may have a substituent, a triphenylmethyl group which may have a substituent, an organosilyl group or a C1-5 acyl group; and A means a specific amine; and a preparation process of the derivative.
                            本发明提供了由下式(I)代表的新型(3R,5S)-3,5,6-三羟基
己酸铵衍
生物:
 其中 R1 代表可能具有取代基的苄基、可能具有取代基的三苯甲基、有机
硅基团或 C1-5 
丙烯酸基团;A 代表特定胺;以及该衍
生物的制备方法。