Stagonospora cirsii是强烈的Cirsium的病原体,在这种有害杂草的叶子上引起坏死性病变。在液体培养中生长时,真菌会产生有毒代谢产物。分离出一种新的植物毒素,命名为staagonolide,并通过光谱法将其表征为(8R,9R)-8-羟基-7-氧代-9-丙基-5-壬烯-9-内酯。Stagonolide被证明是非宿主特异性但选择性的植物毒素。C. arvense的叶子最敏感,而番茄和胡椒(茄科)的叶子对苯二酚的敏感度较低,后者在5 x 10(-3)M的条件下比其他植物更易被检测到。在5 x 10(-6)M下测定的Stagonolide被证明是C. arvense和其他一些菊科植物幼苗中根系生长的强抑制剂。小麦和萝卜的幼苗生长受毒素的影响要小得多,黄瓜的幼苗对此不敏感。
A stereoselectivetotal synthesis of phytotoxic compounds herbarumin I and stagonolide A has been achieved utilizing Crimmin’s protocol for non-Evans anti-aldol approach and a ring-closing olefin metathesis reaction as the key steps. macrolide - phytotoxic - Evans aldol - olefin metathesis
The chemo-enzymatic and covergent synthesis of stagonolide B and the synthesis of stagonolide A, a phytotoxic 10-membered lactone have been achieved starting from D-ribose with overall yields of 25% and 8.7%, respectively. The synthesis contained simple steps in developing three centers' key intermediates, namely the enzymatic (Novozyme-435) resolution of a propargylic alcohol followed by macrolactonization and RCM. (C) 2010 Elsevier Ltd. All rights reserved.
First stereoselective total synthesis of (−)-stagonolide A
The first stereoselective total synthesis of the nonenolide (-)-stagonolide A is described Olefin metathesis and epoxide opening reaction are the key steps involved. (c) 2009 Elsevier Ltd All rights reserved