Enantioselective Synthesis of the C7-C24 Segment of Macrolactin A

Abstract

The C7-C24 tetraene triol segment of macrolactin A was prepared using organoiron chemistry. Two (carbonyl)iron moieties are responsible for stereoselective preparation of the C8-C11 E,Z-diene, as well as the C-15 and C-24 sp³ stereocenters. Furthermore, this iron complexation serves to protect the C8-C11 and C16-C19 diene groups during reductive hydrolysis of an isoxazoline group.

polyene macrolide - (diene)iron complexes - nitrile oxide-olefin cycloaddition - remote asymmetric induction

References

<A NAME="RM01803SS-1A">1a</A> Gustofson K. Roman M. Fenical W. J. Am. Chem. Soc.  1989,  111:  7519 

<A NAME="RM01803SS-1B">1b</A> Rychnovsky SD. Skalitzky DJ. Pathirana C. Jensen PR. Fenical W. J. Am. Chem. Soc.  1992,  114:  671 

<A NAME="RM01803SS-2A">2a</A> Jaruchoktaweechai C. Suwanborirus K. Tanasupawatt S. Kittakoop P. Menasveta P. J. Nat. Prod.  2000,  63:  984 

<A NAME="RM01803SS-2B">2b</A> Nagao T. Adachi K. Sakai M. Nishijima M. Sano H. J. Antibiot.  2001,  54:  333 

<A NAME="RM01803SS-2C">2c</A> Kim H.-H. Kim W.-G. Ryoo I.-J. Kim C.-J. Suk J.-E. Han K.-H. Hwang S.-Y. Yoo I.-D. J. Microbio. Biotech.  1997,  7:  429 

For previous synthetic studies, see:

<A NAME="RM01803SS-3A">3a</A> Benvegnu T. Schio L. Le Floc’h Y. Gree R. Synlett  1994,  505 

<A NAME="RM01803SS-3B">3b</A> Tanimori S. Morita Y. Tsubota M. Nakayama M. Synth. Commun.  1996,  26:  559 

<A NAME="RM01803SS-3C">3c</A> Benvegnu TJ. Toupet LJ. Gree RL. Tetrahedron  1996,  52:  11811 

<A NAME="RM01803SS-3D">3d</A> Benvegnu TJ. Gree RL. Tetrahedron  1996,  52:  11821 

<A NAME="RM01803SS-3E">3e</A> Gonzalez A. Aiguada J. Urpi F. Vilarrasa J. Tetrahedron Lett.  1996,  49:  8949 

<A NAME="RM01803SS-3F">3f</A> Li S. Xu R. Bai D. Tetrahedron Lett.  2000,  41:  3463 

<A NAME="RM01803SS-4A">4a</A> Boyce RJ. Pattenden G. Tetrahedron Lett.  1996,  37:  3501 

<A NAME="RM01803SS-4B">4b</A> Smith AB. Ott GR. J. Am. Chem. Soc.  1998,  120:  3935 

<A NAME="RM01803SS-4C">4c</A> Kim Y. Singer RA. Carreira EM. Angew. Chem. Int. Ed.  1998,  37:  1261 

<A NAME="RM01803SS-5">5</A> Marino JP. McClure MS. Holub DP. Comasseto JV. Tucci FC. J. Am. Chem. Soc.  2002,  124:  1664 

<A NAME="RM01803SS-6">6</A> Bärmann H. Prahlad V. Tao C. Yun YK. Wang Z. Donaldson WA. Tetrahedron  2000,  56:  2289 

<A NAME="RM01803SS-7">7</A> Godula K. Bärmann H. Donaldson WA. J. Org. Chem.  2001,  66:  3590 

<A NAME="RM01803SS-8">8</A> Donaldson WA. Shang L. Tao C. Yun YK. Ramaswamy M. Young VG. J. Organomet. Chem.  1997,  539:  87 

<A NAME="RM01803SS-9">9</A> Howell JAS. Squibb AD. Bell AG. McArdle P. Cunningham D. Goldschmidt Z. Gottlieb HE. Hezroni-Langerman D. Gree R. Organometallics  1994,  13:  4336 

<A NAME="RM01803SS-10">10</A>

2-Trimethylsilylethyl nitroacetate was prepared by Ti(OEt)₄-catalyzed transesterification of ethyl nitroacetate with 2-trimethylsilylethanol (56%).

<A NAME="RM01803SS-11">11</A> Brown HC. Jadhav PK. J. Am. Chem. Soc.  1983,  105:  2092 

<A NAME="RM01803SS-12">12</A> Prahlad V. El-Ahl AS. Donaldson WA. Tetrahedron: Asymmetry  2000,  11:  3091 

<A NAME="RM01803SS-13">13</A> Tomooka K. Okinaga T. Suzuki K. Tsuchihashi G. Tetrahedron Lett.  1988,  29:  2677 

<A NAME="RM01803SS-14">14</A> Mukaiyama T. Hoshino T. J. Am. Chem. Soc.  1960,  82:  5339 

<A NAME="RM01803SS-15">15</A> Dasgupta B. Donaldson WA. Tetrahedron: Asymmetry  1998,  9:  3781 

<A NAME="RM01803SS-16">16</A> Le Gall T. Lellouche J.-P. Toupet L. Beaucourt J.-P. Tetrahedron Lett.  1989,  47:  6517 

<A NAME="RM01803SS-17">17</A> Franck-Neumann F. Geoffroy P. Bissinger P. Adelaide S. Tetrahedron Lett.  2001,  42:  6401 

<A NAME="RM01803SS-18">18</A> Evans DA. Chapman KJ. Carreira EM. J. Am. Chem. Soc.  1988,  110:  3560 

<A NAME="RM01803SS-19A">19a</A> Rychnovsky SD. Skalitzky DJ. Tetrahedron Lett.  1990,  31:  945 

<A NAME="RM01803SS-19B">19b</A> Evans DA. Fieger DL. Gage JR. Tetrahedron Lett.  1990,  31:  7099 

<A NAME="RM01803SS-20">20</A>

Notably, others have reported that removal of hydroxyl protecting groups from intact macrolactin A has proven to be difficult (cf. Ref. [4b] ).

<A NAME="RM01803SS-21">21</A> Pinsard P. Lellouche J.-P. Beaucourt J.-P. Toupet L. Schio L. Gree R. J. Organomet. Chem.  1989,  371:  219