Antibiotics poly ether

Poly ether antibiotic X-206 by E. J. Corey (Harvard University) ... 

Hydroboration of alkenes1 (15, 91). The Rh(I)-catalyzed hydroboration provides a highly diastereoselective reaction in a synthesis of a poly ether antibiotic. Thus the derivative (1) of an acyclic allylic alcohol is converted to the primary alcohol 2 by hydroboration with catecholborane (CB) catalyzed by ClRh[P(C6H5)3]3 with 94 6 selectivity. Note that hydroboration of 1 with disiamylborane (12, 484) proceeds with the opposite selectivity at Cio (8 92). 

Horita, K, Inoue, T, Tanaka, K, Yonemitsu, O, Stereoselective total synthesis of lysocellin, the representative poly ether antibiotic of the lysocellin family. Part 1. Synthesis of C1-C9 and C16-C23 subunits. Tetrahedron, 52, 531-550, 1996. 

Poly ether antibiotics azaphilone mould metabolites. 

In a total synthesis of the poly-ether antibiotic lasalocid A, the key intermediate (5) (Scheme 11) was prepared by sequential epoxidation of the keto-diene (4) subsequent transformations led to synthetic lasalocid A (6). 

Poly ether antibiotics, Yll, Y6 Polyporenic acid A, TSO Polyzonimine, K8 ... 

Development of diastereoselective and enantioselective aldol reactions has had a profound impact on the synthesis of two important classes of natural products—the macrolide antibiotics and the poly ether ionophores. The aldehyde and the enolate involved in aldol reactions can be chiral, but we shall discuss only the case of chiral enolates. 

As noted above, a goal of the lariat ether work was to develop eompounds that might function in a fashion similar to valinomycin. A dozen crown ethers, including two 1.3-xylyl-21-crown-6 macrocyclic poly ether 2-car-boxylic acid lariat ethers, were prepared and tested in vitro for biological activity. Several of the compounds showed activity and are thought to be functional mimics of ionophore antibiotics. 

Polyether A molecule that contains many ether linkages. Poly ethers occur naturally in a number of antibiotic substances. 

Chemical modification of monensin, poly ether ionophoric antibiotic withbound tetrahydropyran, two tetrahydrofuran, and octahydrospiro-2,2 -furopyian fragments 97YZ583. 

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