HETEROCYCLES
An International Journal for Reviews and Communications in Heterocyclic ChemistryWeb Edition ISSN: 1881-0942
Published online by The Japan Institute of Heterocyclic Chemistry
Special Issue
Shun-ichi Yamada's Special Issues, Vol. 46, No. 1, 1997
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■ Facile Diastereoselective Reactions of Chiral 1,3-Oxazolidines with Grignard Reagents; Asymmetric Syntheses of 2-Substituted and 2,6-Disubstituted Piperidines
Hadi Poerwono, Kimio Higashiyama,* Takayasu Yamauchi, and Hiroshi Takahashi
*Faculty of Pharmaceutical Sciences, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan
Abstract
(S)- and (R)-2-Phenylpiperidines, (S)- and (R)-2-methylpiperidines, meso- and (2R, 6R)-2,6-diphenylpiperidines, and meso- and (2S, 6S)-2,6-dimethylpipendines were synthesized asymmetrically starting from the diastereoselective addition of Grignard reagents to chiral 1,3-oxazolidines, converting of 1-aza-4-oxabicyclo[4.3.0]nonane derivatives as pivotal intermediates.
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■ A New Enantiospecific Approach to the Bislactone Structure: Formal Syntheses of (-)-Avenaciolide and (-)-Isoavenaciolide
Katsuji Ito, Tsutomu Fukuda, and Tsutomu Katsuki*
*Department of Chemistry, Faculty of Science, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan
Abstract
A new synthetic methodology for the synthesis of the condensed bislactone structure was developed by using enantiospecific ring expansion of oxetane as a key step. This methodology was proven to be useful for the syntheses of natural products such as (-)-avenaciolide and (-)-isoavenaciolide.
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■ Synthesis of (±)-Nitramine and (±)-Isonitramine by Utilizing Stereoselective Reduction of Ethyl 1-(3-Bromopropyl)-2-oxocyclohexanecarboxylate
Hisanori Senboku, Mamoru Hatazawa, Kazuhiko Orito, and Masao Tokuda*
*Division of Molecular Chemistry, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628, Japan
Abstract
Formal synthesis of (±)-nitramine (1) and (±)-isonitramine (2) was achieved. Thus, the reduction of ethyl 1-(3-bromopropyl)-2-oxocyclohexanecarboxylate (6) with NaBH4 in MeOH gave the wrresponding cyclohexanol (7) having cis geometry between hydroxyl and ester groups, predominantly. On the other hand, the trans located isomer (8) was preferentially obtained by reduction with LiAl(OBut)3H in THF. Treatment of the former reduction product (7) having cis geomehy with benzylamine at 60 °C gave cis located ethyl 1-(3-(N-benzylamino)-propyl)-2-hydroxycyclohexanecarboxylate (9), which was further treated with BuLi to give a spirolactam, 2-benzyl-7-hydroxy-2-azaspiro[5,5]undecan-1-one (11) in 84 % yield. Reduction of the lactam (11) with BH3·SMe2 in THF gave N-benzylnitramine (13). In a similar manner, N-benzylisonitramine (14) was synthesized from trans located hydroxyaminoester (10).
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■ An Expeditious Synthesis of Geodiamolide A, an 18-Membered Cytotoxic Depsipeptide from Marine Sponges
Takayuki Shioiri,* Takayuki Imaeda, and Yasumasa Hamada
*Faculty of Pharmaceutical Sciences, Nagoya City University, Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan
Abstract
Geodiamolide A (1) has been efficiently synthesized from the polypropionate and tripeptide units using the Evans asymmetric alkylation, the Mitsunobu esterification, and the macrolactamization with diphenyl phosphorazidate (DPPA) as key steps. Efficient esterification between the complex polyketide and tripeptide units was also realized under high pressure conditions.
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■ Synthesis of Heteroarenecarbonitriles by Electrophilic Cyanation; Reaction of Metalated Heteroarenes with p-Toluenesulfonyl Cyanide
Izuru Nagasaki, Yumiko Suzuki, Ken-ichi Iwamoto, Takeo Higashino, and Akira Miyashita*
*School of Pharmaceutical Sciences, Shizuoka University, 52-1 Yada, Shizuoka
Abstract
Several heteroarenecarbonitriles (5) were synthesized in moderate yields from heteroarenes (3) through metalation, followed by electrophilic cyanation using p-toluenesulfonyl cyanide. Similarly, trimethylsilylheteroarenes (8) were converted to heteroarenecarbonitriles (5) in good yields by treatment with p-toluenesulfonyl cyanide.
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■ The Photo-Oxygenation of Dihydropyrans. Formation of 1,2-Dioxetanes and 1,2,4-Trioxanes
Charles W. Jefford,* Marcelo Ferrufino Deheza, and Jian Bo Wang
*Department of Organic Chemistry, Laboratory fo Crystallography, University of Geneva, 30, quai Ernest Ansermet, 1211 Geneva 4, Switzerland
Abstract
3,4-Dihydro-2H-pyran (1), 5,6,7,8-tetrahydrochroman (9), and 2-oxabicyclo[4.6.0]dodec-1(6)-ene (13) on dye-sensitized photo-oxygenation give the corresponding 1,2-dioxetanes (3), (10), and (14) in yields of 35-53% as isolable, stable entities with the exception of 10. 2-Hydroperoxy-5,6-dihydro-2H-pyran (5) is also obtained from 1 in 15% yield. No hydroperoxide is formed from 9, whereas 13 affords 3,4,6,7,8,9-hexahydro-2H-cycloocta[b]pyran-4a-yl hydroperoxide (15) in variable, but minor yields depending on the choice of solvent, temperature and sensitizer. Further [2 + 2] addition to 15 produces the 1,2-dioxetane (16). Repetition of the photo-oxygenation of 1, 9 and 13 in the presence of acetaldehyde affords the same products as before. In the case of 1, the cis-fused epimeric 1,2,4-trioxanes (7) are additionally formed in 2% yield. TMSOTf-catalyzed treatment of 3, 10, and 14 with acetaldehyde affords the corresponding 1,2,4-trioxanes in yields of 30, 30 and 43%. Thermolysis of 3, 10, and 14 breaks the dioxetane ring to produce the monocyclic keto lactones.
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■ Electrophilic Heteroatom Cyclization of ω-Alkenylphoshonic Acid Half Esters Giving Cyclic Phosphonates (Phostones)
Tsutomu Yokomatsu, Yoshihito Shioya, Haruo Iwasawa, and Shiroshi Shibuya*
*School of Pharmacy, Tokyo University of Pharmacy and Life Science, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
Abstract
Electrophilic heteroatom cyclizations of v-alkenylphosphonic acid half esters (4a-d) with NBS or phenylselenenyl chloride were examined to give the cyclic phosphonates (phostones) (6a-d and 7a-d). The phenyselenomethylphostone (7c) was converted to the acetoxymethylphostone (9) through sequential seleno-Pummerer rearrangement and reductive deselenenylation.
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■ Synthesis of Conformationally Restrained, β-Substituted Derivatives of L-Tryptophan via Lewis Acid-catalyzed Reaction of 2,3-Aziridino-β-D-lyxo-furanosides with 1-(Trialkylsilyl)indoles
Bernhard Hofmann, Philippe Dauban, Jean-Philippe Biron, Pierre Potier, and Robert H. Dodd*
*Institut de Chimie des Substances Naturelles, Centre National de la Recherche Scientifique, Avenue de la Terrasse, Bat. 27, 91198 Gif-sur-Yvette Cedex, France
Abstract
Reaction of 1-(trisopropylsilyl)indole (or its 5-benzyloxy derivative) with tert-butyldimethylsilyl N-(tert-butyloxycarbonyl)-2,3-aziridino-2,3-dideoxy-5-O-methyl- (or benzyl-)-β-D-lyxofwanoside in the presence of boron trifluoride etherate gave, regio-and stereospecifically, the corresponding protected 2-amino-3-(3-indolyl)arabinofuranoside derivatives. These could be transformed, after desilylation, oxidation and removal of the Boc group, into 2-amino-3-(3-indolyl)arabinonolactone derivatives. The latter represent novel examples of conformationally restrained analogues of L-tryptophan as well as precursors of optically pure β-substituted L-tryptophans.
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■ Fluorescent Bithiophene Chromophores: Synthesis and Application in CD Exciton Chirality Studies
Norihiro Ikemoto, Isabel Estevez, Koji Nakanishi, and Nina Berova*
*Department of Chemistry, Columbia University, New York, NY 10027, U.S.A.
Abstract
Bithiophene chromophores were synthesized and used to derivatize NH2 and OH groups in aminocyclohexane, (1R, 2R)-diaminocyclohexane, (1R, 2R)-trans-1,2-cyclohexanediol and methyl L-acosamidine for their application in the exciton chirality method. Schiff base, ester and amide derivatives were generated in good yields and were found to exhibit exciton-split CD curves. Besides their absorption at long wavelengths (red-shifted) in the visible range, the bithiophene derivatives showed fluorescence and solvatochromic properties.
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■ Reaction of 5-Hydroxyimino-1,3-dioxine-4,6-dione (Isonitroso Meldrum's Acid) with Carbodiimides to Give Parabanic Acids
Nobuya Katagiri,* Yoshihiro Morishita, and Chikara Kaneko
*Pharnaceutical Institute, Tohoku University, Aramaki, Aoba-ku, sendai 980-8578, Japan
Abstract
Reaction of 5-hydroxyimino-1,3-dioxine-4,6-dione (isonitroso Meldrum’s Acid) with carbodiimides gave cyanoformamide derivatives in quantitative yields, which cyclized to iminoparabanic acids and parabanic acids under basic and acidic conditions, respectively.
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■ Association Constants of 5,8,11,14-Tetraoxa-2,17-dithiabicyclo[16.4.1]tricosa-1(22),18,20-trien-23-one for Various Metal Ions
Akira Mori,* Kanji Kubo, and Hitoshi Takeshita*
*Instituete of Advanced Material Study, Kyushu University, 6-1, Kasuga-koen, Kasuga 816-8580, Japan
Abstract
With the regard to the pronounced mercurophilicity of dithio-crown ethers incorporated into seven-membered conjugated systems, the association constants of 5,8,11,14-tetraoxa-2,17-dithiabicyclo[16.4.1]tricosa-1(22),18,20-trien-23-one, the most effective carrier of mercury(II) salt, were determined with various metal salts. An increasing order of the association constants was Na+< K+< NH4+ < Li+ < Mg2+ < Zn2+ < Cd2+ < Hg2+ < Ba2+ < Ca2+ in acetonitrile.
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■ Synthesis of (S)-(+)-α-Methoxymethyldihydrocoumarin: Absolute Configuration of the Reduced Product in Enantioselective Radical-mediated Reduction
Masatoshi Murakata, Hideyuki Tsutsui, and Osamu Hoshino*
*Faculty of Pharmaceutical Sciences, Science University of Tokyo, 12, Ichigaya Funagawara-machi, Shinjuku-ku, Tokyo 162-0826, Japan
Abstract
(S)-(+)-α-Methoxymethyldihydrocoumarin was synthesized starting from (R)-2-benzyl-3-hydroxypropyl acetate. Consequently, the absolute configuration of the reduced product obtained by radical-mediated reduction of α-iodo-α-methoxymethyldihydmcoumarin was determined to be R.
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■ A Novel Route to 4-Aryl-5,6-dihydro-1,2-oxathiin-2,2-dioxides and Related Heterocyclic Systems
Eric Bonfand, William B. Motherwell,* Andrew M. K. Pennell, Muhammed K. Uddin, and Feroze Ujjainwalla
*Department of Chemistry, Christopher Ingold Laboratories, University College London, 20 Gordon Street, London WC1H 0AJ, U.K.
Abstract
The addition of a tri n-butylstannyl radical to arene and heteroarene sulfonate esters of homopropagyl alcohol triggers a sequence of [1,6] ipso-substitution followed by 6-endo addition and elimination to yield unusual 4-aryl-5,6-dihydro-1,2-oxathiin-2,2- dioxides and related heterocyclic systems.
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■ A Facile Asymmetric Synthesis of Corey Lactone Utilizing C2-Symmetric Dimethyl 3,7-Dihydroxy-cis-bicyclo[3.3.0]octan-2,6-diene-2,6-dicarboxylate
Manabu Node,* Daisaku Nakamura, Kiyoharu Nishide, and Takehisa Inoue
*Kyoto Pharmaceutical University, Misasagi, Yamashina, Kyoto 607-8414, Japan
Abstract
Optically pure Corey lactone [(-)-1] was conveniently synthesized from an optically pure C2-symmetric diester [(+)-3] which was prepared by lipase-catalyzed demethoxycabonylation of bicyclic tetraester (2).
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■ Two New Pyrroloquinazolinoquinoline Alkaloids from Peganum nigellastrum
Zhong-Ze Ma, Yoshio Hano, Taro Nomura,* and Ying-Jie Chen
*Faculty of Pharmaceutical Sciences, Toho University, 2-2-1, Miyama, Funabashi, Chiba 274-8510, Japan
Abstract
Two new alkaloids, luotonins A and B, were isolated from the aerial parts of Peganum nigellastrum along with four known quinazoline type alkaloids. The structures of luotoins A and B were determined to be 1 and 2, respectively, by NMR spectroscopic evidence. Both new alkaloids have a unique structure comprising a quinoline and a quinazoline skeletons.
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■ A High Chemical Reactivity of 5-Azidouracils and Its Synthetic Application: Novel Synthesis of 8-Substituted 1,3-Dimethylxanthine Derivatives
Kosaku Hirota,* Magoichi Sako, and Hironao Sajiki
*Labolatory of Medicinal Chemistry, Gifu Pharmaceutical University, 6-1 Mitahora-higashi 5-chome, Gifu 502-8585, Japan
Abstract
A novel method for the preparation of 8-substituted 1,3-dimethylxanthine derivatives (7 or 8) is described: treatment of 6-alkylamino-5-bromo-1,3-dimethyluracils (6a-e), easily prepared by bromination of the corresponding 6-alkylamino-1,3-dimethyluracils (5), with sodium azide in DMF at ambient temperature allowed the direct formation of the 8-substituted 1,3-dimethylxanthines (7) proceeding via a transient formation of the corresponding 5-azido-1,3-dimethyluracils. The 5-bromo-1,3-dimethyluracils (6f, g) possessing an α-branched alkylamino group at the 6-position similarly react with sodium aide to afford 8,8-disubstituted 1,3-dimethyl-8H-xanthines (8,8-disubstituted 1,3-dimethyl-3,8-dihydropurine-2,6-diones) (8).
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■ A Highly Efficient Synthesis of 1-Methyl-, 1-Benzyl-, and 1-Phenyl-1,2,3,4-tetrahydroisoquinolines by a Modified Pummerer Reaction
Tatsumi Shinohara, Akira Takeda, Jun Toda, Noriyo Terasawa, and Takehiro Sano*
*Showa Pharmaceutical University, 3-3165, Higashi-tamagawagakuen, Machida, Tokyo 194-8543, Japan
Abstract
(±)-1-Methyl- (13b), (±)-1-benzyl- (13c), and (±)-1-phenyl- (13d)-1,2,3,4-tetrahydroisoquinolines, which are supposed to participate in the pathogenesis of Parkinson’s disease, were prepared by using a modified Pummerer reaction as a key step in excellent overall yields from the commercially available ketones (4b-c).
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■ Coumarin-containing Amino Acids and Oxy Acids as Chiral Discriminating Agents. Part III. Novel Crystalline (R)-(+)- and (S)-(-)-O-Coumarinyl Lactic Acids as Chiral Derivatizing Agents for 1H NMR Inspection of Optical Purities of Alcohols and Amines
Kazuo Nagasawa, Noriko Seto, and Keiichi Ito*
*Hokkaido College of Pharmacy, 7-1 Katsuraoka-cho, Otaru 047-02, Japan
Abstract
Comercially available (S)-(-)-ethyl lactate and (R)-(+)-methyl lactate were quite simply coupled with comercia1 4-hydroxycoumarin by the Mitsunobu reaction followed by alkaline hydrolysis to furnish new crystalline optically pure (R)-(+)-and (S)-(-)-O-coumrinyllactic acids[RCLOH and SCLOH] in good yields. Diastereomeric esters and amides derived easily and quantitatively from these acids were subjected to chiral shift 1H NMR examination, revealing that these were efficient and reliable chiral derivatizing agents. Either racemization or kinetic resolution was not induced during derivatization.
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■ Synthesis of (2S*,4R*,5S*)-Piperidinetricarboxylic Acid, a Non-proteinogenic Amino Acid Isolated from Clitocybe acromelalga
Kimiko Hashimoto, Shuhei Higashibayashi, and Haruhisa Shirahama*
*School of Science, Kwansei Gakuin University, 1-1-155 Uegahara, Nishinomiya 662-8501, Japan
Abstract
(2S*,4R*,5S*)-Piperidinetricarboxylic acid isolated from a poisonous mushroom Clitocybe acromelalea was synthesized along with its stereoisomers and their depolarizing activity was tested.
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■ Studies on Water-soluble Artificial Receptors Containing Chiral Side Chains Derived from Carbohydrates. 1. Synthesis of Optically Active Cyclophane TCP44 and Its Complexation Selectivity for Aromatic Guests in Acidic Aqueous Solutions
Ichiro Takahashi, Yuuki Hirano, Hiroshi Arakawa, Hidehiko Kitajima, Minoru Hatanaka, Kimio Isa, Kazunori Odashima,* and Kenji Koga*
*Graduate School of Pharmaceutical Science, University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-0033
Abstract
The details of the synthesis and complexation properties of L-tartrate-derived cyclophane (TCP44), the first totally synthetic host with a chiral hydrophobic cavity, are described. The synthesis employs 1:1 cyclization via a U-shaped precursor containing chiral C4 units derived from L-tartaric acid. TCP44, soluble in acidic water as an amine salt, displayed a complexation selectivity for hydrophobic aromatic guests. Inclusion of aromatic guests into the cavity was verified by fluorescence and 1H NMR spectra. A possible structure of inclusion cavity is discussed.
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■ Diastereofacial Selectivity of Radical Cyclization Using Chiral α,β-Unsaturated Ester and Amide: Investigation of a New Chiral Synthon Synthesis
Akira Katsumata, Takehiko Iwaki, Keiichiro Fukumoto, and Masataka Ihara*
*Pharnaceutical Institute, Tohoku University, Aramaki, Aoba-ku, sendai 980-8578, Japan
Abstract
The chiral α,β-unsaturated ester (3a) gave cyclic acetal (4aA) in a highly diastereoselective manner (>98% de) by radical cyclization, which was carried out in the presence of MAD. Furthermore, 4aA was converted into chiral lactone (9), possessing the stereogenic center with three differentiated C-2 units.
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■ New Methodology for the Synthesis of α,α-Dialkylamino Acids Using the "Self-Regeneration of Stereocenters" Method: α-Ethyl-α-phenylglycine
Martin J. O'Donnell,* Zhiqiang Fang, Xiaojun Ma, and John C. Huffman
*Department of Chemistry, Indiana University-Purdue University at Indianapolis, Indianapolis, IN 46202, U.S.A.
Abstract
The stereoselective room temperature ethylations of protected oxazolidinones from phenylglycine by phase-transfer catalysis or with KOtBu as base are used to prepare optically active α-ethyl-α-phenylglycine.
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■ A Short Asymmetric Synthesis of (-)-Neonepetalactone
Dieter Enders* and Anja Kaiser
*Institut für Organische Chemie, Rheinisch-Westfälische, Technische Hochsch, Professor-Pirlet-Strasse 1, D-52074 Aachen, Germany
Abstract
(4S,4aR)-Neonepetalactone (6) was synthesized in high diastereomeric and enantiorneric purity (de, ee > 96 %) in a four step procedure. Key step of the total synthesis is the Michael addition of metalated propanal SAMP-hydrazone ((S)-1) to 2-cyclopentenecarboxylate (2).
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■ Improved Synthesis of 1-Deoxynojirimycin and Facile Synthesis of Its Stereoisomers from (S)-Pyroglutamic Acid Derivative
Nobuo Ikota, * Jun-ichi Hirano, Ranjith Gamage, Hidehiko Nakagawa, and Hiroko Hama-Inaba
*National Institute of radiological Sciences, 9-1, Anagawa-4-Chome, Inage-ku, Chiba 263, Japan
Abstract
Improved synthesis of 1-deoxynojirimycin (9) from (E)-α,β-unsaturated ester (1) and facile synthesis of 1-deoxyazasugars (14 and 15) from 10 where both substrates (1 and 10) prepared from (S)-pyroglutamic acid were described.
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■ Correlation of 15N NMR Chemical Shifts with Calculated Partial Charges in Pyridine N-Oxides
Kiyoshi Matsumoto,* Mona Ciobanu, Takane Uchida, and Takahisa Machiguchi
*Graduate School of Human and Environmental Studies, Kyoto University, Yoshida-Nihonmatsu-cho, Sakyo-ku, Kyoto 606-8501, Japan
Abstract
p-Substituted pyridine N-oxides have been found very good linear correlations between the 15N NMR chemical shifts and the partial charges, obtained by semiempirical molecular orbital methods.
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■ Synthesis of Water-soluble Diaza-1,2,5-thiadiazolocyclophanes
Taizo Hatta,* Muneo Kawano, Yuji Imaizumi, Akihiko Tsuge, Tetsuji Moriguchi, Hironori Maeda, and Otohiko Tsuge*
*Department of Industrial Chemistry, Kumamoto Institute of Technology, 4-22-1, Ikeda, Kumamoto
Abstract
The reaction of 3,4-bis(p-bromomethyIphenyl)-1,2,5-thiadiazole(1) with bis(N-alkylaminomethyl)benzenes under high dilution conditions gave the diaza-1,2,5-thiadiazolo[3.3.2]cyclophanes, while 1 reacted with xylylenediamines to give cupped diazathiadiazolocyclophanes as major products. The reaction of 1 with the amino analog of 1 furnished the diaza-1,2,5-thiadiazolo[3.2.3.2]cyclophane in an excellent yield. These diazacyclophanes were soluble in acidic media.
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■ 1'-Methyl-trans-zeatin and Its Analogues: Their Occurrence, Chemistry and Synthesis, and Cytokinin Activity
Tozo Fujii,* Taisuke Itaya, and Masashi Ohba
*Faculty of Pharmaceutical Scicences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan
Abstract
Recent advances in isolation, structure establishment, chemistry and synthesis, and evaluation of cytokinin activity of the title compounds are reviewed with 45 reference citations.
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■ Total Synthesis of Fumitremorgins and Verruculogens
Tohru Hino and Masako Nakagawa*
*Faculty of Pharmaceutical Sciences, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan
Abstract
The syntheses of fumitremorgin B(49b), C(54), verruculogen TR-2(101), and related compounds, all of which pentacyclic tremorgenic mycotoxins are reviewed. Major topics include construction of the pentacyclic ring system, stereoselective formation of 1,3-disubstituted β-carboline, introduction of a double bond and cis=glycol to the ring C of the pentacycle.
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■ Synthetic Studies on Heteroanthracyclines
Masayuki Kirihara and Yasuyuki Kita*
*Faculty of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Toyonaka, Osaka 560-0043, Japan
Abstract
This review summarizes the synthetic studies on the new anthracycline analogs which have heterocyclic ring systems in their aglycones.
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■ Studies towards the Total Synthesis of Taxoids: Strategies Built around a Molecule and the Discovery of New Methodologies
Siméon Arseniyadis,* Rosemeire Brondi Alves, Rossimiriam Pereira de Freitas, Manuel Muñoz Dorado, Dmitry V. Yashunsky, Pierre Potier, and Loïc Toupet
*Institut des Chimie des Substances Naturelles, C.N.R.S., Avenue de la Terrasse, Bat. 27, 91198 Gif-sur-Yvette Cedex, France
Abstract
We describe below the evolution of a three-reaction (aldol-annelationfragmentation) based strategy as well as the discovery of Ph(OAc)4 mediated cascade reactions towards the total synthesis of the taxoid diterpene skeleton (1).