... (m, 22 H), 0. 92 (t, 3H); 13C NMR (300 MHz, C6D6) δ 154.8, 94.6, 85.6, 80 .2, 79.7, 79 .2, 65.0, 64 .2, 63.8, 63 .2, 62. 8, 61.9, 32. 0, 29 .8, 29 .6, 29 .4, 29 .2, 28 .9, 28 .7, 28 .0, 25 .8, 25 .4, 23 .2, 22 .7, ... 64.44% 72. 98% 63.88% Structures of six obtained compounds (analogues of sphingosine) 2. 2 .2 Compounds Inhibitory Function on SPHK Activity in vitro 2. 2 .2. 1 Over-expression of SPHK1 and SPHK2 2. 2 .2. 1.1 ... specific inhibitors for SPHK, and even isotype-specific (SPHK1 vs SPHK2) With the newly developed inhibitors, a better understanding of the role of SPHK in the process of stem cells differentiation...