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Current Organic Chemistry

Editor-in-Chief

ISSN (Print): 1385-2728
ISSN (Online): 1875-5348

Book Reviews

Synthetic Approaches Towards Taxol; from Holton to Chida

Author(s): Mohamed F. Elmansy*, Rita M. Borik and Rizk E. Khidre*

Volume 27, Issue 5, 2023

Published on: 13 June, 2023

Page: [444 - 459] Pages: 16

DOI: 10.2174/1385272827666230512114730

Abstract

Nature is an inspiring source in drug discovery which constantly reveals new complex chemical structures of natural products that inherit attractive chemical challenges for organic chemists to synthesize them. Taxol is a unique natural product that impressive biological properties and a very tempting chemical structure that motivated organic chemists all over the world to enter the race for synthesizing it. The total synthesis of this highly oxygenated diterpene was completed by 11 different research groups starting from Holton (1994) to Chida (2022). This review article demonstrates the various retrosynthetic analysis of Taxol, the actual synthetic routes to it and highlights the key steps in each synthesis. It also provides a critical review of the advantages and disadvantages in all the synthetic routes in terms of number of steps, yields and the synthetic challenges.

Keywords: Taxol® or paclitaxel, Holton’s route, retrosynthetic, Diels-Alder reaction, synthetic routes, natural product.

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[1]
Wani, M.C.; Taylor, H.L.; Wall, M.E.; Coggon, P.; McPhail, A.T. Plant antitumor agents. VI. Isolation and structure of taxol, a novel antileukemic and antitumor agent from Taxus brevifolia. J. Am. Chem. Soc., 1971, 93(9), 2325-2327.
[http://dx.doi.org/10.1021/ja00738a045] [PMID: 5553076]
[2]
Kim, S.H.; Kim, M.J.; Kim, Y.J.; Chang, H.; Kim, J.W.; Lee, J.O.; Lee, K.W.; Kim, J.H.; Bang, S.M.; Lee, J.S. Paclitaxel as third-line chemotherapy for small cell lung cancer failing both etoposide- and camptothecin-based chemotherapy. Medicine (Baltimore), 2017, 96(42), e8176.
[http://dx.doi.org/10.1097/MD.0000000000008176] [PMID: 29049199]
[3]
Li, Q.; Ma, Z.; Liu, Y.; Kan, X.; Wang, C.; Su, B.; Li, Y.; Zhang, Y.; Wang, P.; Luo, Y.; Na, D.; Wang, L.; Zhang, G.; Zhu, X.; Wang, L. Low doses of paclitaxel enhance liver metastasis of breast cancer cells in the mouse model. FEBS J., 2016, 283(15), 2836-2852.
[http://dx.doi.org/10.1111/febs.13767] [PMID: 27307301]
[4]
Schiff, P.B.; Fant, J.; Horwitz, S.B. Promotion of microtubule assembly in vitro by taxol. Nature, 1979, 277(5698), 665-667.
[http://dx.doi.org/10.1038/277665a0] [PMID: 423966]
[5]
Danishefsky, S.J.; Masters, J.J.; Young, W.B.; Link, J.T.; Snyder, L.B.; Magee, T.V.; Jung, D.K.; Isaacs, R.C.A.; Bornmann, W.G.; Alaimo, C.A.; Coburn, C.A.; Di Grandi, M.J. Total synthesis of baccatin III and taxol. J. Am. Chem. Soc., 1996, 118(12), 2843-2859.
[http://dx.doi.org/10.1021/ja952692a]
[6]
Holton, R.A.; Somoza, C.; Kim, H.B.; Liang, F.; Biediger, R.J.; Boatman, P.D.; Shindo, M.; Smith, C.C.; Kim, S. First total synthesis of taxol. 1. Functionalization of the B ring. J. Am. Chem. Soc., 1994, 116(4), 1597-1598.
[http://dx.doi.org/10.1021/ja00083a066]
[7]
Holton, R.A.; Kim, H.B.; Somoza, C.; Liang, F.; Biediger, R.J.; Boatman, P.D.; Shindo, M.; Smith, C.C.; Kim, S. First total synthesis of taxol. 2. Completion of the C and D rings. J. Am. Chem. Soc., 1994, 116(4), 1599-1600.
[http://dx.doi.org/10.1021/ja00083a067]
[8]
Holton, R.A.; Juo, R.R.; Kim, H.B.; Williams, A.D.; Harusawa, S.; Lowenthal, R.E.; Yogai, S. A synthesis of taxusin. J. Am. Chem. Soc., 1988, 110(19), 6558-6560.
[http://dx.doi.org/10.1021/ja00227a043]
[9]
Davis, F.A.; Chen, B.C. Asymmetric hydroxylation of enolates with N-sulfonyloxaziridines. Chem. Rev., 1992, 92(5), 919-934.
[http://dx.doi.org/10.1021/cr00013a008]
[10]
Omura, K.; Swern, D. Oxidation of alcohols by “activated” dimethyl sulfoxide. a preparative, steric and mechanistic study. Tetrahedron, 1978, 34(11), 1651-1660.
[http://dx.doi.org/10.1016/0040-4020(78)80197-5]
[11]
Lee, S.D.; Chan, T.H.; Kwon, K.S. Rearrangement of α-acyloxyacetates into 2-hydroxy-3-ketoesters. Tetrahedron Lett., 1984, 25(32), 3399-3402.
[http://dx.doi.org/10.1016/S0040-4039(01)91030-5]
[12]
Atkins, G.M., Jr; Burgess, E.M. The reactions of an N-sulfonylamine inner salt. J. Am. Chem. Soc., 1968, 90(17), 4744-4745.
[http://dx.doi.org/10.1021/ja01019a052]
[13]
Griffith, W.P.; Ley, S.V.; Whitcombe, G.P.; White, A.D. Preparation and use of tetra-n-butylammonium per-ruthenate (TBAP reagent) and tetra-n-propylammonium per-ruthenate (TPAP reagent) as new catalytic oxidants for alcohols. J. Chem. Soc. Chem. Commun., 1987, (21), 1625.
[http://dx.doi.org/10.1039/c39870001625]
[14]
Nicolaou, K.C.; Yang, Z.; Liu, J.J.; Ueno, H.; Nantermet, P.G.; Guy, R.K.; Claiborne, C.F.; Renaud, J.; Couladouros, E.A.; Paulvannan, K.; Sorensen, E.J. Total synthesis of taxol. Nature, 1994, 367(6464), 630-634.
[http://dx.doi.org/10.1038/367630a0] [PMID: 7906395]
[15]
Shapiro, R.H.; Lipton, M.F.; Kolonko, K.J.; Buswell, R.L.; Capuano, L.A. Tosylhydrazones and alkyllithium reagents: More on the regiospecificity of the reaction and the trapping of three intermediates. Tetrahedron Lett., 1975, 16(22-23), 1811-1814.
[http://dx.doi.org/10.1016/S0040-4039(00)75263-4]
[16]
McMurry, J.E.; Fleming, M.P. New method for the reductive coupling of carbonyls to olefins. Synthesis of. beta.-carotene. J. Am. Chem. Soc., 1974, 96(14), 4708-4709.
[http://dx.doi.org/10.1021/ja00821a076] [PMID: 4850242]
[17]
Nicolaou, K.C.; Liu, J.J.; Hwang, C.K.; Dai, W.M.; Guy, R.K. Synthesis of a fully functionalized CD ring system of taxol. J. Chem. Soc. Chem. Commun., 1992, (16), 1118.
[http://dx.doi.org/10.1039/c39920001118]
[18]
Nicolaou, K.C.; Hwang, C.K.; Soresen, E.J.; Clairborne, C.F. A convergent strategy towards taxol. A facile enantioselective entry into a fully functionalized ring A system. J. Chem. Soc. Chem. Commun., 1992, (16), 1117.
[http://dx.doi.org/10.1039/c39920001117]
[19]
Nicolaou, K.C.; Yang, Z.; Sorensen, E.J.; Nakada, M. Synthesis of ABCtaxoid ring systems via a convergent strategy. J. Chem. Soc. Chem. Commun., 1993, (12), 1024.
[http://dx.doi.org/10.1039/c39930001024]
[20]
Brown, H.C. Hydroboration—a powerful synthetic tool. Tetrahedron, 1961, 12(3), 117-138.
[http://dx.doi.org/10.1016/0040-4020(61)80107-5]
[21]
Corey, E.J.; Suggs, J.W. Pyridinium chlorochromate. An efficient reagent for oxidation of primary and secondary alcohols to carbonyl compounds. Tetrahedron Lett., 1975, 16(31), 2647-2650.
[http://dx.doi.org/10.1016/S0040-4039(00)75204-X]
[22]
Wieland, P.; Miescher, K. Über die Herstellung mehrkerniger Ketone. Helv. Chim. Acta, 1950, 33(7), 2215-2228.
[http://dx.doi.org/10.1002/hlca.19500330730]
[23]
Hickmott, P.W.; Hopkins, B.J. Enamine chemistry. Part IV. Reaction of αβ-unsaturated acid chlorides with enamines of aldehydes. J. Chem. Soc. C, 1968, 0(0), 2918-2924.
[http://dx.doi.org/10.1039/J39680002918]
[24]
Corey, E.J.; Chaykovsky, M. Dimethyloxosulfonium Methylide ((CH 3) 2 SOCH 2) and Dimethylsulfonium Methylide ((CH3)2SCH2). Formation and Application to Organic Synthesis. J. Am. Chem. Soc., 1965, 87(6), 1353-1364.
[http://dx.doi.org/10.1021/ja01084a034]
[25]
Greene, A.E.; Muller, J.C.; Ourisson, G. A new approach to α-methylene-γ-butyrolactones. II. Synthesis of (+)-arbusculin-B. Tetrahedron Lett., 1972, 13(32), 3375-3378.
[http://dx.doi.org/10.1016/S0040-4039(01)94049-3]
[26]
Grieco, P.A.; Gilman, S.; Nishizawa, M. Organoselenium chemistry. A facile one-step synthesis of alkyl aryl selenides from alcohols. J. Org. Chem., 1976, 41(8), 1485-1486.
[http://dx.doi.org/10.1021/jo00870a052]
[27]
Barton, D.H.R.; Bashiardes, G.; Fourrey, J.L. Studies on the oxidation of hydrazones with iodine and with phenylselenenyl bromide in the presence of strong organic bases; An improved procedure for the synthesis of vinyl iodides and phenyl-vinyl selenides. Tetrahedron, 1988, 44(1), 147-162.
[http://dx.doi.org/10.1016/S0040-4020(01)85102-4]
[28]
Wender, P.A.; Badham, N.F.; Conway, S.P.; Floreancig, P.E.; Glass, T.E.; Gra, C.; Houze, J.B.; Ja, J.; Lee, D.; Marquess, D.G.; Mcgrane, P.L.; Meng, W.; Mucciaro, T.P.; Mu, M.; Natchus, M.G.; Paulsen, H.; Rawlins, D.B.; Satkofsky, J.; Shuker, A.J.; Sutton, J.C.; Taylor, R.E.; Tomooka, K. The pinene path to taxanes. 5. Stereocontrolled synthesis of a versatile taxane precursor. J. Am. Chem. Soc., 1997, 119(11), 2755-2756.
[29]
Wender, P.A.; Mucciaro, T.P. A new and practical approach to the synthesis of taxol and taxol analogs: The pinene path. J. Am. Chem. Soc., 1992, 114(14), 5878-5879.
[http://dx.doi.org/10.1021/ja00040a070]
[30]
Erman, W.F. Photochemical transformations of unsaturated bicyclic ketones. Verbenone and its photodynamic products of ultraviolet irradiation. J. Am. Chem. Soc., 1967, 89(15), 3828-3841.
[http://dx.doi.org/10.1021/ja00991a026]
[31]
Hurst, J.J.; Whitham, G.H. 579. The photochemistry of verbenone. J. Chem. Soc., 1960, 2864, 2864.
[http://dx.doi.org/10.1039/jr9600002864]
[32]
Moore, R.N.; Golumbic, C.; Fisher, G.S. Autoxidation of α-Pinene 2. J. Am. Chem. Soc., 1956, 78(6), 1173-1176.
[http://dx.doi.org/10.1021/ja01587a022]
[33]
Gilman, H.; Jones, R.G.; Woods, L.A. The preparation of methylcopper and some observations on the decomposition of organocopper compounds. J. Org. Chem., 1952, 17(12), 1630-1634.
[http://dx.doi.org/10.1021/jo50012a009]
[34]
Dess, D.B.; Martin, J.C. Readily accessible 12-I-5 oxidant for the conversion of primary and secondary alcohols to aldehydes and ketones. J. Org. Chem., 1983, 48(22), 4155-4156.
[http://dx.doi.org/10.1021/jo00170a070]
[35]
Crabtree, R.H.; Davis, M.W. Directing effects in homogeneous hydrogenation with [Ir(cod)(PCy3)(py)]PF6. J. Org. Chem., 1986, 51(14), 2655-2661.
[http://dx.doi.org/10.1021/jo00364a007]
[36]
Takano, S.; Inomata, K.; Samizu, K.; Tomita, S.; Yanase, M.; Suzuki, M.; Iwabuchi, Y.; Sugihara, T.; Ogasawara, K. A convenient one-flask synthesis of α-methylenealdehydes from primary alcohols. Chem. Lett., 1989, 18(7), 1283-1284.
[http://dx.doi.org/10.1246/cl.1989.1283]
[37]
Johansen, J.E.; Piermattie, V.; Angst, C.; Diener, E.; Kratky, C.; Eschenmoser, A. Interconversion of the chromophore systems of porphyrinogen and 2,3,7,8,12,13-hexahydroporphyrin. Angew. Chem. Int. Ed. Engl., 1981, 20(3), 261-263.
[http://dx.doi.org/10.1002/anie.198102611]
[38]
Ojima, I.; Habus, I.; Zhao, M.; Zucco, M.; Park, Y.H.; Sun, C.M.; Brigaud, T. New and efficient approaches to the semisynthesis of taxol and its C-13 side chain analogs by means of β-lactam synthon method. Tetrahedron, 1992, 48(34), 6985-7012.
[http://dx.doi.org/10.1016/S0040-4020(01)91210-4]
[39]
Kusama, H.; Hara, R.; Kawahara, S.; Nishimori, T.; Kashima, H.; Nakamura, N.; Morihira, K.; Kuwajima, I. Enantioselective total synthesis of (−)-taxol. J. Am. Chem. Soc., 2000, 122(16), 3811-3820.
[http://dx.doi.org/10.1021/ja9939439]
[40]
Birch, A.J. 117. Reduction by dissolving metals. Part I. J. Chem. Soc., 1944, 430, 430.
[http://dx.doi.org/10.1039/jr9440000430]
[41]
Nelson, D.W.; Gypser, A.; Ho, P.T.; Kolb, H.C.; Kondo, T.; Kwong, H.L.; McGrath, D.V.; Rubin, A.E.; Norrby, P.O.; Gable, K.P.; Sharpless, K.B. Toward an understanding of the high enantioselectivity in the osmium-catalyzed asymmetric dihydroxylation. 4. Electronic effects in amine-accelerated osmylations. J. Am. Chem. Soc., 1997, 119(8), 1840-1858.
[http://dx.doi.org/10.1021/ja961464t]
[42]
Peterson, D.J. Carbonyl olefination reaction using silyl-substituted organometallic compounds. J. Org. Chem., 1968, 33(2), 780-784.
[http://dx.doi.org/10.1021/jo01266a061]
[43]
Mukaiyama, T.; Shiina, I.; Iwadare, H.; Saitoh, M.; Nishimura, T.; Ohkawa, N.; Sakoh, H.; Nishimura, K.; Tani, Y.; Hasegawa, M.; Yamada, K.; Saitoh, K. Asymmetric total synthesis of taxol. Chemistry, 1999, 5(1), 121-161.
[http://dx.doi.org/10.1002/(SICI)1521-3765(19990104)5:1<121:AID-CHEM121>3.0.CO;2-O]
[44]
Nelson, C.G.; Burke, T.R. Jr Samarium iodide-mediated Reformatsky reactions for the stereoselective preparation of β-hydroxy-γ-amino acids: Synthesis of isostatine and dolaisoleucine. J. Org. Chem., 2012, 77(1), 733-738.
[http://dx.doi.org/10.1021/jo202091r] [PMID: 22136325]
[45]
Snyder, J.P. Mechanism of lithium cuprate conjugate addition: Neutral tetracoordinate cui cuprates as essential intermediates. J. Am. Chem. Soc., 1995, 117(44), 11025-11026.
[http://dx.doi.org/10.1021/ja00149a033]
[46]
Swindell, C.S.; Chander, M.C.; Heerding, J.M.; Klimko, P.G.; Rahman, L.T.; Raman, V.; Venkataraman, H. Taxane synthesis through intramolecular pinacol coupling at C-1−C-2. Construction and oxidative transformations of a c-aromatic taxane diene. J. Org. Chem., 1996, 61(3), 1101-1108.
[http://dx.doi.org/10.1021/jo951935e]
[47]
Doi, T.; Fuse, S.; Miyamoto, S.; Nakai, K.; Sasuga, D.; Takahashi, T. A formal total synthesis of taxol aided by an automated synthesizer. Chem. Asian J., 2006, 1(3), 370-383.
[http://dx.doi.org/10.1002/asia.200600156] [PMID: 17441074]
[48]
Watanabe, H.; Iwamoto, M.; Nakada, M. Preparation of new chiral building blocks: highly enantioselective reduction of prochiral 1,3-cycloalkanediones possessing a methyl group and a protected hydroxymethyl group at their C2 position with baker’s yeast or CBS catalyst. J. Org. Chem., 2005, 70(12), 4652-4658.
[http://dx.doi.org/10.1021/jo050349a] [PMID: 15932301]
[49]
Iwamoto, M.; Miyano, M.; Utsugi, M.; Kawada, H.; Nakada, M. Development of silicon-tethered anionic reaction and its application to the synthesis of chiral A-ring moieties of Taxol™. Tetrahedron Lett., 2004, 45(47), 8647-8651.
[http://dx.doi.org/10.1016/j.tetlet.2004.09.143]
[50]
Kawada, H.; Iwamoto, M.; Utsugi, M.; Miyano, M.; Nakada, M. Synthetic studies on the taxane skeleton: construction of eight-membered carbocyclic rings by the intramolecular B-alkyl Suzuki-Miyaura cross-coupling reaction. Org. Lett., 2004, 6(24), 4491-4494.
[http://dx.doi.org/10.1021/ol0481939] [PMID: 15548058]
[51]
Nakada, M.; Kojima, E.; Iwata, Y. A concise synthesis approach to optically active taxol C-ring fragment. Tetrahedron Lett., 1998, 39(3-4), 313-316.
[http://dx.doi.org/10.1016/S0040-4039(97)10554-8]
[52]
Iwamoto, M.; Kawada, H.; Tanaka, T.; Nakada, M. Preparation of new chiral building blocks via asymmetric catalysis. Tetrahedron Lett., 2003, 44(39), 7239-7243.
[http://dx.doi.org/10.1016/j.tetlet.2003.08.009]
[53]
Utsugi, M.; Iwamoto, M.; Hirai, S.; Kawada, H.; Nakada, M. Formal total synthesis of (−)-taxol. J. Synth. Org. Chem. Jpn., 2017, 75(11), 1102-1114.
[http://dx.doi.org/10.5059/yukigoseikyokaishi.75.1102]
[54]
Hirai, S.; Utsugi, M.; Iwamoto, M.; Nakada, M. Formal total synthesis of (-)-taxol through Pd-catalyzed eight-membered carbocyclic ring formation. Chemistry, 2015, 21(1), 355-359.
[http://dx.doi.org/10.1002/chem.201404295] [PMID: 25346263]
[55]
Stork, G.; Hudrlik, P.F. Isolation of ketone enolates as trialkylsilyl ethers. J. Am. Chem. Soc., 1968, 90(16), 4462-4464.
[http://dx.doi.org/10.1021/ja01018a051]
[56]
Takai, K.; Nitta, K.; Utimoto, K. Simple and selective method for aldehydes (RCHO). fwdarw. (E)-haloalkenes (RCH:CHX) conversion by means of a haloform-chromous chloride system. J. Am. Chem. Soc., 1986, 108(23), 7408-7410.
[http://dx.doi.org/10.1021/ja00283a046]
[57]
Comprehensive Organic Name Reactions and Reagents; John Wiley & Sons, Inc.: Hoboken, NJ, USA, 2010.
[http://dx.doi.org/10.1002/9780470638859.conrr483]
[58]
Mendoza, A.; Ishihara, Y.; Baran, P.S. Scalable enantioselective total synthesis of taxanes. Nat. Chem., 2012, 4(1), 21-25.
[http://dx.doi.org/10.1038/nchem.1196] [PMID: 22169867]
[59]
Kanda, Y.; Nakamura, H.; Umemiya, S.; Puthukanoori, R.K.; Appala, V.R.M.; Gaddamanugu, G.K.; Paraselli, B.R.; Baran, P. Two-Phase Synthesis of Taxol®. ChemRxiv, 2020.
[http://dx.doi.org/10.26434/chemrxiv.12061620.v1]
[60]
Davis, E.M.; Croteau, R. Cyclization enzymes in the biosynthesis of monoterpenes; Sesquiterpenes, and Diterpenes, 2000, pp. 53-95.
[http://dx.doi.org/10.1007/3-540-48146-X_2]
[61]
Winkler, J.D.; Kim, H.S.; Kim, S. A highly efficient synthesis of taxanes via the tandem Diels-Alder reaction. Tetrahedron Lett., 1995, 36(5), 687-690.
[http://dx.doi.org/10.1016/0040-4039(94)02353-D]
[62]
Rubenstein, S.M.; Williams, R.M. Studies on the Biosynthesis of Taxol: Total Synthesis of Taxa-4(20),11(12)-diene and Taxa-4(5),11(12)-diene. The First Committed Biosynthetic Intermediate. J. Org. Chem., 1995, 60(22), 7215-7223.
[http://dx.doi.org/10.1021/jo00127a029]
[63]
Brown, P.A.; Jenkins, P.R. Synthesis of the taxane ring system using an intramolecular Diels–Alder reaction of a 2-substituted diene. J. Chem. Soc., Perkin Trans. 1, 1986, (0), 1303-1309.
[http://dx.doi.org/10.1039/P19860001303]
[64]
Bear, B.R.; Sparks, S.M.; Shea, K.J. The type 2 intramolecular diels-alder reaction: synthesis and chemistry of bridgehead alkenes. Angew. Chem. Int. Ed., 2001, 40(5), 820-849.
[http://dx.doi.org/10.1002/1521-3773(20010302)40:5<820:AID-ANIE820>3.0.CO;2-F] [PMID: 11241630]
[65]
Magnus, P.; Westwood, N.; Spyvee, M.; Frost, C.; Linnane, P.; Tavares, F.; Lynch, V. Taxane diterpenes 5: Synthesis of the A- and C-rings: An unusual rearrangement of an N-hydroxyimino lactone. Tetrahedron, 1999, 55(21), 6435-6452.
[http://dx.doi.org/10.1016/S0040-4020(99)00305-1]
[66]
Petersson, M.J.; Marchal, C.; Loughlin, W.A.; Jenkins, I.D.; Healy, P.C.; Almesåker, A. Unexpected regiospecific reactivity of a substituted phthalic anhydride. Tetrahedron, 2007, 63(6), 1395-1401.
[http://dx.doi.org/10.1016/j.tet.2006.11.090]
[67]
Vuagnoux-d’Augustin, M.; Alexakis, A. Copper-catalyzed asymmetric conjugate addition of trialkylaluminium reagents to trisubstituted enones: construction of chiral quaternary centers. Chemistry, 2007, 13(34), 9647-9662.
[http://dx.doi.org/10.1002/chem.200701001] [PMID: 17849404]
[68]
Kobayashi, S.; Hachiya, I.; Yamanoi, Y. Repeated use of the catalyst in Ln(OTf) 3-Catalyzed aldol and allylation reactions. Bull. Chem. Soc. Jpn., 1994, 67(8), 2342-2344.
[http://dx.doi.org/10.1246/bcsj.67.2342]
[69]
Wilde, N.C.; Isomura, M.; Mendoza, A.; Baran, P.S. Two-phase synthesis of (-)-taxuyunnanine D. J. Am. Chem. Soc., 2014, 136(13), 4909-4912.
[http://dx.doi.org/10.1021/ja501782r] [PMID: 24625050]
[70]
Hu, Y.J.; Gu, C.C.; Wang, X.F.; Min, L.; Li, C.C. Asymmetric total synthesis of taxol. J. Am. Chem. Soc., 2021, 143(42), 17862-17870.
[http://dx.doi.org/10.1021/jacs.1c09637] [PMID: 34641680]
[71]
Fukaya, K.; Tanaka, Y.; Sato, A.C.; Kodama, K.; Yamazaki, H.; Ishimoto, T.; Nozaki, Y.; Iwaki, Y.M.; Yuki, Y.; Umei, K.; Sugai, T.; Yamaguchi, Y.; Watanabe, A.; Oishi, T.; Sato, T.; Chida, N. Synthesis of Paclitaxel. 1. Synthesis of the ABC ring of paclitaxel by SmI2-mediated cyclization. Org. Lett., 2015, 17(11), 2570-2573.
[http://dx.doi.org/10.1021/acs.orglett.5b01173] [PMID: 26010812]
[72]
Iiyama, S.; Fukaya, K.; Yamaguchi, Y.; Watanabe, A.; Yamamoto, H.; Mochizuki, S.; Saio, R.; Noguchi, T.; Oishi, T.; Sato, T.; Chida, N. Total synthesis of paclitaxel. Org. Lett., 2022, 24(1), 202-206.
[http://dx.doi.org/10.1021/acs.orglett.1c03851] [PMID: 34904840]
[73]
Luche, J.L. Lanthanides in organic chemistry. 1. Selective 1,2 reductions of conjugated ketones. J. Am. Chem. Soc., 1978, 100(7), 2226-2227.
[http://dx.doi.org/10.1021/ja00475a040]
[74]
Luche, J.L.; Rodriguez-Hahn, L.; Crabbé, P. Reduction of natural enones in the presence of cerium trichloride. J. Chem. Soc. Chem. Commun., 1978, 0(14), 601-602.
[http://dx.doi.org/10.1039/C39780000601]
[75]
El-Mansy, M.F.; Donaldson, W.A. Recent advances in the synthesis of taxoids: 2015-2020. ARKIVOC, 2021, 2021(5), 110-137.
[http://dx.doi.org/10.24820/ark.5550190.p011.494]

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