Syntheses of Conjugated Pyrones for the Enzymatic Assay of Lovastatin Nonaketide Synthase, an Iterative Polyketide Synthase
摘要:
Lovastatin nonaketide synthase (LovB, LNKS) is an iterative type I polyketide synthase (PKS) from Aspergillus terreus that produces dihydromonacolin L (2), the biosynthetic precursor of lovastatin (1), from acetyl CoA, malonyl CoA, and S-adenosylmethionine (SAM) if the accessory protein LovC is present. In the absence of LovC, LNKS forms the conjugated pyrones 3 and 4 as truncated PKS products. Short syntheses of these pyrones provide material for the assay of LNKS activity by HPLC and radioisotope dilution analysis.
Syntheses of Conjugated Pyrones for the Enzymatic Assay of Lovastatin Nonaketide Synthase, an Iterative Polyketide Synthase
摘要:
Lovastatin nonaketide synthase (LovB, LNKS) is an iterative type I polyketide synthase (PKS) from Aspergillus terreus that produces dihydromonacolin L (2), the biosynthetic precursor of lovastatin (1), from acetyl CoA, malonyl CoA, and S-adenosylmethionine (SAM) if the accessory protein LovC is present. In the absence of LovC, LNKS forms the conjugated pyrones 3 and 4 as truncated PKS products. Short syntheses of these pyrones provide material for the assay of LNKS activity by HPLC and radioisotope dilution analysis.
3‐Acyltetramic acids, including delicate 3‐oligoenoyl derivatives, such as the Penicillium metabolite ravenicacid, were prepared in two high‐yielding steps. Reaction of tetramicacids with the ylide Ph3PCCO afforded exclusively the corresponding 3‐acylylidenetetramic acids. These were amenable to Wittig olefinations with aliphatic, aromatic, saturated and unsaturated aldehydes after deprotonation
3-Acyltetramic acid,包括易碎的3-oligoenoyl衍生物,例如青霉代谢产物鼠尾草酸,是通过两个高产率步骤制备的。丁二酸与叶立德Ph 3 PCCO的反应仅提供了相应的3-酰亚乙基四丁酸。这些在用KO t Bu去质子化之后适合于用脂族,芳族,饱和和不饱和醛进行的维蒂希(Wittig)烯化。由于其简单性,对pH敏感基团的选择性和耐受性,该方法优于Jones和Yoshii建立的酰化方案。它也适用于3-酰基电子酸的合成。新的3-寡烯酰基四酸显示出结构依赖性的抗微生物和细胞毒性活性。
Syntheses of Conjugated Pyrones for the Enzymatic Assay of Lovastatin Nonaketide Synthase, an Iterative Polyketide Synthase
作者:Douglas A. Burr、Xuan B. Chen、John C. Vederas
DOI:10.1021/ol062763i
日期:2007.1.1
Lovastatin nonaketide synthase (LovB, LNKS) is an iterative type I polyketide synthase (PKS) from Aspergillus terreus that produces dihydromonacolin L (2), the biosynthetic precursor of lovastatin (1), from acetyl CoA, malonyl CoA, and S-adenosylmethionine (SAM) if the accessory protein LovC is present. In the absence of LovC, LNKS forms the conjugated pyrones 3 and 4 as truncated PKS products. Short syntheses of these pyrones provide material for the assay of LNKS activity by HPLC and radioisotope dilution analysis.