Efficient Generation of a Trisporoid Library by Combination of Synthesis and Biotransformation
摘要:
[GRAPHIC]Trisporic acids and their biosynthetic precursors represent a family of powerful fungal pheromones and morphogenetic factors. A highly flexible synthetic protocol is described that (i) provides rapid access to nonfunctionalized early trisporoids from beta-ionone, (ii) includes a regiospecific oxidative functionalization of beta-ionone leading to 1-acetoxy-beta-ionone giving access to functionalized trisporoids, and (iii) utilizes a biotransformation of early synthetic trisporoids by growing cells of Blakeslea trispora to prepare late trisporoids including trisporic acids. The same protocol also provides deuterium-labeled trisporoids such as trisporin B [H-2(3)]-19. Administration of [H-2(3)]-19 to growing cells of the (-)-mating type of B. trispora resulted in the formation of the labeled trisporols [H-2(3)]-20 and [H-2(3)]-21. Growing cultures containing both mating types can be used to prepare trisporic acids from early precursors.
Efficient Generation of a Trisporoid Library by Combination of Synthesis and Biotransformation
摘要:
[GRAPHIC]Trisporic acids and their biosynthetic precursors represent a family of powerful fungal pheromones and morphogenetic factors. A highly flexible synthetic protocol is described that (i) provides rapid access to nonfunctionalized early trisporoids from beta-ionone, (ii) includes a regiospecific oxidative functionalization of beta-ionone leading to 1-acetoxy-beta-ionone giving access to functionalized trisporoids, and (iii) utilizes a biotransformation of early synthetic trisporoids by growing cells of Blakeslea trispora to prepare late trisporoids including trisporic acids. The same protocol also provides deuterium-labeled trisporoids such as trisporin B [H-2(3)]-19. Administration of [H-2(3)]-19 to growing cells of the (-)-mating type of B. trispora resulted in the formation of the labeled trisporols [H-2(3)]-20 and [H-2(3)]-21. Growing cultures containing both mating types can be used to prepare trisporic acids from early precursors.
In the course of their sexual interactions, zygomycete fungi communicate via an elaborate series of carotene-derived compounds, namely trisporic acid and its biosynthetic progenitors. A novel building-block strategy allowed the systematic generation of structurally modified trisporoids along with putative early biosynthetic precursors for physiological tests. The impact of discrete structural elements was documented by the ability of individual compounds to induce sexually committed hyphae in Mucor mucedo. The activity screening contributed to establish general structure-function relationships for trisporoid action. Most crucial for activity were the dimension of the longer side chain, the polarity of functional groups at C(4) and C(13), and the number of conjugated double bonds in the side chain. The presence of an oxygen substituent at the cyclohexene ring is not essential for function. The overall biological activity apparently results from the combination of the various structural elements. (c) 2005 Elsevier Ltd. All rights reserved.