3-(2-(2,4-dihydroxy-6-methylphenyl)-2-oxoethyl)-6,8-dihydroxy-1H-isochromen-1-one | 1004112-69-9

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: 3-(2-(2,4-dihydroxy-6-methylphenyl)-2-oxoethyl)-6,8-dihydroxy-1H-isochromen-1-one
• 英文别名: SMA93；Bikisocoumarin；3-[2-(2,4-dihydroxy-6-methylphenyl)-2-oxoethyl]-6,8-dihydroxyisochromen-1-one
• CAS: 1004112-69-9
• 化学式: C₁₈H₁₄O₇
• 分子量: 342.305
• InChiKey: DKXXSCXXPYENDD-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  3.2
• 重原子数：
  25
• 可旋转键数：
  3
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.11
• 拓扑面积：
  124
• 氢给体数：
  4
• 氢受体数：
  7

反应信息

• 作为产物：
  描述：

  sodium malonate 在 megasynthase PKS₄-99 、 Rhizobium trifolii malonyl-CoA synthase MatB 、 5’-三磷酸腺苷 、 辅酶 A 、 magnesium chloride 、 1,4-二巯基-2,3-丁二醇 作用下， 反应 12.0h， 生成 3-(2-(2,4-dihydroxy-6-methylphenyl)-2-oxoethyl)-6,8-dihydroxy-1H-isochromen-1-one
  参考文献：
  名称：

  Classification, Prediction, and Verification of the Regioselectivity of Fungal Polyketide Synthase Product Template Domains

  摘要：

  The fungal iterative nonreducing polyketide synthases (NRPKSs) synthesize aromatic polyketides, many of which have important biological activities. The product template domains (PT) embedded in the multidomain NRPKSs mediate the regio-selective cyclization of the highly reactive polyketide backbones and dictate the final structures of the products. Understanding the sequence-activity relationships of different PT domains is therefore an important step toward the prediction of polyketide structures from NRPKS sequences and can enable the genome mining of hundreds of cryptic NRPKSs uncovered via genome sequencing. In this work, we first performed phylogenetic analysis of PT domains from NRPKSs of known functions and showed that the PT domains can be classified into five groups, with each group corresponding to a unique product size or cyclization regioselectivity. Group V contains the formerly unverified PT domains that were identified as C6-C11 aldol cyclases. The regioselectivity of PTs from this group were verified by product-based assays using the PT domain excised from the asperthecin AptA NRPKS. When combined with dissociated PKS4 minimal PKS, or replaced the endogenous PKS4 C2-C7 PT domain in a hybrid NRPKS, AptA-PT directed the C6-C11 cyclization of the nonaketide backbone to yield a tetracyclic pyranoanthraquinone 4. Extensive NMR analysis verified that the backbone of 4 was indeed cyclized with the expected regioselectivity. The PT phylogenetic analysis was then expanded to include similar to 100 PT sequences from unverified NRPKSs. Using the assays developed for AptA-PT, the regioselectivities of additional PT domains were investigated and matched to those predicted by the phylogenetic classifications.

  DOI：

  10.1074/jbc.m110.128504