- Total synthesis of (R)-sarkomycin via asymmetric rhodium-catalyzed conjugate addition
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(R)-Sarkomycin was prepared using a five-step total synthesis. Key steps in the enantioselective construction of the targeted scaffold were a rhodium-catalyzed asymmetric conjugate alkenyl addition with subsequent silyl trapping and a Mukaiyama aldol reaction with aqueous formaldehyde. Protection of the hydroxy group as a THP acetal and oxidative cleavage of the C,C-double bond provided a stable direct precursor to the natural product. The final liberation was carried out under slightly acidic conditions in a microwave-assisted reaction, resulting in a high yield of the deceptive sarkomycin. This represents the shortest enantioselective synthesis of this rather unstable compound to date and the first to employ asymmetric catalysis to introduce the stereogenic center.
- Westmeier, Johannes,Kress, Steffen,Pfaff, Christopher,Von Zezschwitz, Paultheo
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p. 10718 - 10723
(2013/11/19)
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- A simple synthesis of (±)-sarkomycin
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A facile 6-step route to (±)-sarkomycin in 17% overall yield has been described via Michael addition of nitromethane to 2-hydroxymethyl-2- cyclopentenone, oxone-induced oxidative Nef reaction, and acid catalyzed dehydration. Georg Thieme Verlag Stuttgart.
- Kar, Anirban,Argade, Narshinha P.
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p. 1234 - 1236
(2007/10/03)
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- Compound having effect of promoting neuron differentiation
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A novel cystacycline derivative which has an excellent effect of promoting the differentiation of neurons and is useful as a remedy for central nervous system disorders, a remedy for peripheral nerve disorders, etc.
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- Total synthesis of racemic and optically active sarkomycin
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trans-3-Carboxy-2-diethoxyphosphorylcyclopentanone (11), a key precursor of sarkomycin 1, has been synthesized in the rhodium(II) acetate promoted cyclization of diethyl 1-diazo-2-oxohept-6-enephosphonate (9), followed by transformation of the 3-vinyl moi
- Miko?ajczyk, Marian,Zurawiński, Remigiusz,Kie?basin?ski, Piotr,Wieczorek, Micha? W.,B?aszczyk, Jaros?aw,Majzner, Wies?aw R.
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p. 356 - 365
(2007/10/03)
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- α-PHOSPHORYL CYCLOPENTANONES AS POSSIBLE INTERMEDIATES IN THE TOTAL SYNTHESIS OF SARKOMYCIN
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In an effort to synthesize sarkomycin 1 trans-2-diphenylphosphinoyl-3-tris(methylthio)methyl-cyclopentanone 7 and trans-2-diphenylphosphinoyl-3-carbomethoxy-cyclopentanone 8 were prepared.The Horner-Wittig reaction of the latter with formaldehyde failed.
- Mikolajczyk, Marian,Kielbasinski, Piotr,Zurawinski, Remigtusz,Wieczorek, Michal W.
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- A NEW SYNTHESIS OF (+/-)-SARKOMYCIN FROM A β-KETOPHOSPHONATE
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The total synthesis of (+/-)-sarkomycin starting from diehtyl 2-oxopropanephosphonate is reported.The key step in this synthesis includes the Horner-Wittig reaction of 2-diethoxy-phosphoryl-3-carboxy-cyclopentanone with formaldehyde
- Mikolajczyk, Marian,Zurawinski, Remigiusz,Kielbasinski, Piotr
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p. 1143 - 1146
(2007/10/02)
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- -Sigmatropic Rearrangement of an in Situ Prepared Ylide and a Thioether to Thio Ester Conversion as Key Steps in Short Syntheses of Sarkomycin and Its Phenylthio Ester
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2-cyclopent-2-en-1-one (2), which is readily available by the reaction of 2-cyclopentenone with thiophenol, formaldehyde, and triethylamine, is transformed, in high yield and moderate conversion by treatment with (trimethylsilyl)methyl triflate, cesium fluoride, and benzaldehyde, to 2-methylene-3-cyclopentanone (3), which, by the use of trichloroisocyanuric acid (Chloreal), can be quantitatively dichlorinated on the sulfur-bearing carbon atom to 3--2-methylenecyclopentanone (4).This dichloro thioether could be hydrolyzed in good yield to a mixture of sarkomycin phenyl thio ester (5) and sarkomycin (6), containing mainly the former; an additional small amount of sarkomycin can be obtained by hydrolysis of the thio ester in the presence of silver trifluoroacetate and benzhydrol.This procedure represents one of the shortest extant syntheses of sarkomycin and a sarkomycin ester.Model studies of the dichlorination of n-octyl phenyl sulfide (8) to 1-(phenylthio)-1,1-dichlorooctane (9) and various transformations of the latter are also reported.
- Cohen, Theodore,Kosarych, Zenyk,Suzuki, Kunio,Yu, Lin-Chen
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p. 2965 - 2968
(2007/10/02)
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- Simple Routes to Sarkomycin
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Two synthetic routes to sarkomycin (6) are demonstrated.The first involves a 3-carbon annelation to form the spirocyclopentenone (2) followed by regiospecific γ-alkylation and subsequent manipulation of the side chain in 15 to give the sarkomycin ester adduct 18.The second route employs the itaconate-anthracene adduct 20 as the C-5 synthon in a tandem Michael addition-Dieckmann condensation between the anion derived from 20 and methyl acrylate.The reaction furnishes the diester 22, which, upon selective decarboxylation, gives rise to the sarkomycin precursors 18 and 23 (1:3).Flash vacuum pyrolysis of either isomer 18 or 23 yields (+/-)-sarkomycin ester 7 which is then hydrolyzed to the acid 6.
- Kodpinid, Montree,Siwapinyoyos, Tiwa,Thebtaranonth, Yodhathai
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p. 4862 - 4865
(2007/10/02)
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- CONJUGATE ADDITION TO THE ETHYLENE KETAL OF 2-CARBOMETHOXY-2-CYCLOPENTENONE A SYNTHESIS OF SARKOMYCIN
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1,4-addition of nitronate anions to the title ketal ester (III) is described; one of the adducts is converted to sarkomycin.
- Hewson, Alan T.,MacPherson, David T.
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p. 647 - 648
(2007/10/02)
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- Regiospecific Synthesis of Sarkomycin and Some Analogues
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The first regiospecific total synthesis of the anticancer compound sarkomycin (1) is described.The starting material is 2-(carbomethoxycyclopent-2-enone (4), a useful precursor for cyclopentanoid natural products.The cyano derivative 5, the amide derivative 6, and the keto lactone 9 were also synthetized.The latter may be considered as a "cyclized" form of sarkomycin and was shown to open slowly to the natural product upon treament with dilute acid.
- Marx, John N.,Minaskanian, Gevork
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p. 3306 - 3310
(2007/10/02)
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- Efficient Enantioselective Synthesis of the Antitumor Agent Sarkomycin
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An efficient total synthesis of (+/-)-sarkomycin (1) is described via bicyclic lactone 8.Preparation of a key precursor (R)-(+)-6 via an asymmetric Diels-Alder reaction affords the correct enantiomer for the preparation of natural (R)-(-)-sarkomycin (1) in high optical yield.
- Boeckman, Robert K.,Naegely, Paul C.,Arthur, Samuel D.
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p. 752 - 754
(2007/10/02)
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