An efficient new synthesis has been elaborated for non-natural (−)-dactylolide ((−)-2) and its 13-desmethylene analogue 4, employing a HWE-based macrocyclization approach with β-keto-phosphonate/aldehyde 19 and the respective 13-desmethylene derivative as the key intermediates. Both (−)-2 and 4 as well as the corresponding C20 alcohols inhibit human cancer cell proliferation with IC50 values in the
A new totalsynthesis of the marine macrolide (−)‐zampanolide (1) and the structurally and stereochemically related non‐natural levorotatory enantiomer of (+)‐dactylolide (2), that is, ent‐2, has been developed. The synthesis features a high‐yielding, selective intramolecular Horner–Wadsworth–Emmons (HWE) reaction to close the 20‐membered macrolactone ring of 1 and ent‐2. The β‐keto phosphonate/aldehyde
已经开发了一种新的海洋大环内酯(-)-樟脑内酯(1)以及结构和立体化学相关的非天然左旋对映异构体(+)-内酯(2)(即ent - 2)的新合成方法。合成有高产,选择性分子内霍纳-沃兹沃思-埃蒙斯(HWE)反应以关闭的20元大环内酯1和ENT - 2。β-酮膦酸酯/醛用于闭环反应的前体是通过将ω-二乙基膦酰基羧酸片段和带有THP环的仲醇片段酯化而获得的,THP环嵌入在1和ent - 2的大环核结构中。THP环的形成是通过片段偶联Prins型环化完成的。采用相同的整体策略,13- desmethylene- ENT - 2以及4的单环desTHP衍生物1个ENT - 2制备。合成1通过n M IC 50抑制人癌细胞的体外生长值ent - 2缺少含二烯的半胱氨酸连接侧链1,而其活性降低了25到260倍。13 Desmethylene- ENT - 2以及减小的版本ENT - 2和13-desmethylene-