The rate of racemization of N(α)-phthalimidoglutarimide (thalidomide) was determined as its half life to be 566 min at pH 7.4/37°C. This fast racemization of thalidomide resulted in no apparent difference between (S)- and (R)-forms of the compound on enhancing activity of phorbol ester-induced tumor necrosis factor (TNF)-α production by human leukemia HL-60 cells. Optically pure forms of structurally related analog of thalidomide, (S)- and (R)-α -methyl-N(α)-phthalimidoglutarimides (methylthalidomides), which do not racemize under the physiological condition, were prepared. Only (S)-form of methylthalidomide, but not its (R)-form, elicited TNF-α production-enhancing effect, suggesting that the (S)-isomer of thalidomide would be the active form in terms of thalidomidal biological response modifying effects.
经测定,N(α)-邻苯二甲酰亚
氨基戊二
酰亚胺(
沙利度胺)在 pH 值为 7.4/37°C 时的半衰期为 566 分钟。
沙利度胺的这种快速外消旋化导致该化合物的(S)-型和(R)-型在增强人白血病 HL-60 细胞产生由光滑脂诱导的肿瘤坏死因子(TNF)-α 的活性方面没有明显差异。制备出了结构相关的沙利度
胺类似物(S)-和(R)-α-甲基-N(α)-邻苯二甲
酰亚胺戊二
酰亚胺(甲基邻苯二甲
酰亚胺)的光学纯形式,它们在生理条件下不会发生外消旋。只有(S)-形式的甲
酞胺而不是其(R)-形式的甲
酞胺能引起TNF-α生成增强效应,这表明甲
酞胺的(S)-异构体是具有甲
酞胺
生物反应调节作用的活性形式。