Tridentoquinone (1), the main pigment of Suillus tridentinus, is accompanied by the known meroterpenoid bolegrevilol (3) and a dimer, tridentorubin (5). The absolute configuration of 1 was unambiguously established by a single-crystal X-ray analysis of the corresponding (–)-camphanoate. The structure of 5 was elucidated by 2D NMR techniques including a 2D INADEQUATE experiment. Feeding experiments
The initial step in the biosynthesis of suillin (1), boviquinone-4 (2) and bovilactone-4,4 (3) in Suillus species is the geranylgeranylation of 3,4-dihydroxybenzoic acid at the 2-position. Feeding experiments with advanced precursors have identified boviquinone-4 and deacetylsuillin (9) as building blocks for the dilactone and catechol moieties, respectively, of bovilactone-4,4 (3). In order to explain
An Effective Method for the Synthesis of<sup>13</sup>C-Labeled Polyprenylhydroxybenzoic Acids
作者:Wolfgang Steglich、Martin Lang
DOI:10.1055/s-2005-861863
日期:——
The synthesis of side-chain 13C-labeled geranylgeranyl-4-hydroxybenzoic acids and geranylgeranyl-3,4-dihydroxybenzoic acids is described. The synthesis starts from O-protected methyl hydroxyiodobenzoates, which are transformed into Grignard reagents by low-temperature iodine-magnesium exchange according to Knochel’s procedure. Copper catalyzed cross-coupling with labeled geranylgeranyl bromide followed by deprotection affords the products with good yields and full retention of stereochemistry.
On the mechanism of ophiobolin F synthase and the absolute configuration of its product by isotopic labelling experiments
作者:Zhiyang Quan、Jeroen S. Dickschat
DOI:10.1039/d0ob01470b
日期:——
An ophiobolin F synthase homolog was discovered fromAspergilluscalidoustus CBS121601. The cyclisation mechanism of this terpene synthase was investigated by extensive isotopic labelling experiments and the absolute configuration of its product ophiobolin F was elucidated by enantioselective deuteration.
从Aspergillus calidoustus CBS121601中发现了 ophiobolin F 合酶同源物。通过广泛的同位素标记实验研究了该萜烯合酶的环化机制,并通过对映选择性氘化阐明了其产物蛇毒蛋白 F 的绝对构型。