@article{60162b5e2c564e0da9ebe77ac887d71c,
title = "Total Synthesis of Herbimycin A",
abstract = "The first total synthesis of herbimycin A (1), the benzoquinoid ansamycin antibiotic, has been accomplished by coupling two segments of the aliphatic ansa-chain 2 and the aromatic chromophore 3, elucidating the absolute stereochemistry.",
keywords = "Ansamycin Antibiotic, Herbimycin A, Regioselective Epoxide-ring Opening, Stereoselective Hydroboration, [(Z-γ-Methoxyallyl]diisopinocampheylborane",
author = "Masaya Nakata and Tomomasa Osumi and Ari Ueno and Takenori Kimura and Tetsuro Tamai and Kuniaki Tatsuta",
note = "Funding Information: Acknowledgment: We are grateful to the Institute of mcroblal Chemistry for the generous support of our program Financial support by the Mmlstry of Education, Science and Culture (Grant-m-Ald for Scientific Research)1 sg ratefullya cknowledged. We thankM ss ma Aolcl for her technicala ssistance References and notes 1 a) S Omum, Y Iwai, Y Takahashl. N Sadakane.A Nakagawa. H Olwa, Y Hasegawa, and T Ikrtl, J Antlblot ,3i, 255 (1979) b) S On&a, A Nakagawa, and R Sadakane,? etrahedr& Left, 1979,4323 c) A Furusalu, T Matsumoto, A Nakagawa, and S Omura, J Antlbrot ,33,781 (1980) d) Y Iwru, A Nakagawa, N Sadakane, S Omura, H Olwa, S Matsumoto, M Takahashl, T Ikal, and Y Ochlal, J Annbzot ,33, 1114 (1980) e) Y Uehara, M HOI-I, T Takeuchl, and H Umezawa, Jpn J Cancer Res (Gann), 76, 672 (1985), K Shlbata, S SatsumabayashrA, Nakagawa, and S Omura, J Antrbrot, 39, 1630 (1986) 2 a) Baker and Casuo have reportedt he first total synthesiso f (+)-macbecmI which has the methyl subshtuent instead of the methoxyl subsutuento n C6 m herblmycm A (l), see R Baker and J L Castro, J Chem Sot , Chem Commun , 1989, 378, J Chem Sot , Perkrn Trans I, 1990, 47 b) Formal synthesis of racennc macbecm I S J Coutts, M D Wlttman, and J Kallmerten, Tetrahedron Lett ,31,4301 (1990), S J Coutts and J Kallmerten, Tetrahedron Len, 31,4305 (1990) K Tatsuta, Y Koguchi, and M Kase, BUN Chem Sot Jpn ,61, 2525 (1988) The rano of the reglolsomersc hangedw th reducmgr eagentsThe detiulsw dl be pubhshedm a full account H C Brown and N M Yoon, J Am Chem Sot ,90, 2686 (1968) Satisfactory analytical data (elemental analyses, 1H NMR and IR spectra) were obtained for all new compounds It has beenr eportedt hatthe bulky reagentse xhibitedl mpresslves tereoselectlvltyg lvmg the ana-1,3-&ols m hydroboratlon of the allyhc alcohol like 10 W C Still and J C Bamsh, J Am Chem Sot ,105,2 487 (1983), I Paterson, C K McClure, and R C Schumann,T etrahedron Left, 30, 1293 (1989) Actually, hydroboranono f 10 usmg &cyclohexylboraneg avet he undesiredC lO-epuner predommantly( 4 5 1) 8 The configurauona t the newly createdC lO-stereucenterw as determmedb y analyang the coupling constants (JlO,l 1 = 2 4 Hz, Jl 1,12 = 8 2 Hz) of the lH NMR spectrum of the benzyhdene denvaave 12, whose benzyhdener mg had a ngd chau conformation The numbermgs ystemu sed for 1 ISe mployedm the &scusaon of all synthetici ntermediates PO D B Dess and J C Martm, J Or-g Chem, 48,4155 (1983) 11 E J Corey, D Enders, and M G Bock, Tetrahedron Left, 1976, 7, R H Schlessmger, M A Poss, S Richardson, and P Lm, Tetrahedron Left, 26,239l (1985) 12 H C Brown, P K Jadhav, and K S Bhat, J Am Chem Sot, 110, 1535 (1988) 13 On the other hand, under the Keck or Koreeda{\textquoteright}s con&tlons14 [MeOCH=CHCH2Sn(n_Bu)3, BF3*Et20], the dlastereomencs yn-dlol was obtameda s a maJor product (4 7 1) The details will be pubhshedm a full account 14 G E Keck, D E Abbott, and M R Wiley, Tetrahedron Lett ,28, 139 (1987), M Koreeda and Y Tanaka, Tetrahedron Len, 28, 143 (1987) 15 The configuranons at the C6 and C7 stereocentersw ere presumedt o be the desired ones m analogy to the well-establishedB rown precedentl 2 16 V Guay and P Brassard, J Heterocycl Chem ,24, 1649 (1987) 17 The Cl5 configuration of 16 was assumedt o be the desired one by comparisono f lH NMR spectrumwith thato f herblmycmA 18 S Yamaguchl and H S Mosher, J Org Chem ,38, 1870 (1973) 19 Coutts and Kallmerten have reported2 b tharL lAlH4 reductiono f their own ketone gave the desued alcohol with a slight excess (1 2 1) selecavlty W C St11a1n d C Gennan, Tetrahedron Lett ,24,4405 (1983) ;: Thw reagent was developed by Palomo-Co11[ J Diago-Meseguer, A L Palomo-Coil, J R Femandez-Lizarbe, and A Zugaza-Bilbao, Syntheas, 1980, 5471 and applied to macrolactarnizaflonm macbecm synthesisb y Baker 2a We also employedt his reagentf or the first total synthesiso f nfamycm W 22 22 M Nakata, N Alayama, K KoJima, H Masuda, M Kmosluta, and K Tatsuta, Tetrahedron Lett , 31, 1585 (1990), M Nakata, N Alayama, J Kamata, K KoJima, H Masuda, M Kmoshlta, and K Tatsuta, Tetrahedron, 46,4629 (1990) B Loev and M F Kormendy, J Org Chem ,28, 3421 (1963) ?i C D Snyder and H Rapoport, J Am Chem Sot (94,227 (1972) See also ref 22 25 We are Indebted to Dr Tornlo Takeuchl, the Institute of Microbial Chemistry, for a generous gift of herbimycmA",
year = "1991",
month = oct,
day = "14",
doi = "10.1016/S0040-4039(00)79452-4",
language = "English",
volume = "32",
pages = "6015--6018",
journal = "Tetrahedron Letters",
issn = "0040-4039",
publisher = "Elsevier Limited",
number = "42",
}