173209-00-2Relevant academic research and scientific papers
Stereochemical analysis of α1, a mating hormone of the phytopathogen Phytophthora
Ojika, Makoto,Qi, Jianhua,Kito, Yuko,Sakagami, Youji
, p. 1763 - 1765 (2007)
The stereochemistry of α1, the first identified mating hormone of the plant pathogen Phytophthora, has been unknown due to its acyclic flexible nature. Here, two stereogenic centers of α1 are determined to be (3RS,15R)-configuration by NMR analysis of the
Total Synthesis of the Alleged Structure of Crenarchaeol Enables Structure Revision**
Cunha, Ana V.,Havenith, Remco W. A.,Holzheimer, Mira,Minnaard, Adriaan J.,Schouten, Stefan,Sinninghe Damsté, Jaap S.
supporting information, p. 17504 - 17513 (2021/07/06)
Crenarchaeol is a glycerol dialkyl glycerol tetraether lipid produced exclusively in Archaea of the phylum Thaumarchaeota. This membrane-spanning lipid is undoubtedly the structurally most sophisticated of all known archaeal lipids and an iconic molecule in organic geochemistry. The 66-membered macrocycle possesses a unique chemical structure featuring 22 mostly remote stereocenters, and a cyclohexane ring connected by a single bond to a cyclopentane ring. Herein we report the first total synthesis of the proposed structure of crenarchaeol. Comparison with natural crenarchaeol allowed us to propose a revised structure of crenarchaeol, wherein one of the 22 stereocenters is inverted.
3,6-DIAMINO-PYRIDAZIN-3-YL DERIVATIVES, PHARMACEUTICAL COMPOSITIONS CONTAINING THEM AND THEIR USES AS PRO-APOPTOTIC AGENTS
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Page/Page column 102-104, (2021/02/05)
Compounds of formula (I) wherein Het1, Het2, R1, R2 and R3 are as defined in the description. Medicaments.
Total synthesis, proof of absolute configuration, and biosynthetic origin of stylopsal, the first isolated sex pheromone of strepsiptera
Lagoutte, Roman,?ebesta, Petr,Jiro?, Pavel,Kalinová, Blanka,Jiro?ová, Anna,Straka, Jakub,?erná, Kate?ina,?obotník, Jan,Cva?ka, Josef,Jahn, Ullrich
supporting information, p. 8515 - 8524 (2013/07/11)
The asymmetric total synthesis of the diastereomers of stylopsal establishes the absolute configuration of the first reported sex pheromone of the twisted-wing parasite Stylops muelleri as (3R,5R,9R)-trimethyldodecanal. The key steps for the diastereo- and enantiodivergent introduction of the methyl groups are two different types of asymmetric conjugate addition reactions of organocopper reagents to α,β-unsaturated esters, whereas the dodecanal skeleton is assembled by Wittig reactions. The structure of the natural product was confirmed by chiral gas chromatography (GC) techniques, GC/MS and GC/electroantennography (EAD) as well as field tests. An investigation into the biosynthesis of the pheromone revealed that it is likely to be produced by decarboxylation of a 4,6,10-trimethyltridecanoic acid derivative, which was found in substantial amounts in the fat body of the female, but not in the host bee Andrena vaga. This triple-branched fatty acid precursor thus seems to be biosynthesized de novo through a polyketide pathway with two consecutive propionate-propionate-acetate assemblies to form the complete skeleton. The simplified, motionless and fully host-dependent female exploits a remarkable strategy to maximize its reproductive success by employing a relatively complex and potent sex pheromone. Love at first.i??-smell: An asymmetric total synthesis, gas chromatographic analyses, and field tests confirm the structure of the first isolated sex pheromone of a twisted-wing parasite Stylops muelleri (see figure). Its biosynthetic origin and complexity demonstrate the considerable efforts undertaken by the motionless and fully host-dependant female to attract the very short-lived free-living male, thus securing success in the perpetuation of the species. Copyright
Highly enantioselective rhodium-catalyzed hydrogenation of 2-(2-methoxy-2-oxoethyl)acrylic acid - A convenient access of enantiomerically pure isoprenoid building blocks
Ostermeier, Markus,Brunner, Bernhard,Korff, Christian,Helmchen, Guenter
, p. 3453 - 3459 (2007/10/03)
Asymmetric catalytic hydrogenation of 2-(2-methoxy-2-oxoethyl)acrylic acid (5) to give (2S)-4-methoxy-2-methyl-4-oxobutanoic acid [(S)-6] was studied. An enantiomeric excess of 99.7% ee was achieved with a catalyst formed in situ from [Rh(COD)2]BF4 and the chiral phosphite L2 in 1,2-dichloroethane as solvent. In addition, enzyme-catalyzed semi-saponification of dimethyl 2-methylsuccinate was investigated. Mono ester (S)-6 was transformed into a few compounds which can serve as C 5-building blocks in natural product syntheses. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.
Synthetic studies toward potent cytotoxic agents amphidinolides G and H: Synthesis of the entire C15-C26 moiety of the top half
Chakraborty,Suresh
, p. 7775 - 7778 (2007/10/03)
Stereoselective synthesis of the entire (16S, 18S, 21R, 22S, 23R, 25R)- C15-C26 segment 1 of amphidinolides G and H has been achieved for the first time following a highly efficient convergent strategy.
Absolute stereostructure of callystatin A, a potent cytotoxic polyketide from the marine sponge, Callyspongia truncata
Murakami, Nobutoshi,Wang, Weiqi,Aoki, Masashi,Tsutsui, Yasuhiro,Higuchi, Kouichi,Aoki, Shunji,Kobayashi, Motomasa
, p. 5533 - 5536 (2007/10/03)
The unidentified configurations at C5 and C10 incallystatin A (1), a potent cytotoxic polyketide from the marine sponge Callyspongia truncata, were determined to be R,R by comparing the circular dichroism spectrum of 1 with those of two model compounds 2 and 3. Compounds 2 and 3 were synthesized by using E-selective Wittig olefination at the C6-C7 position as a key reaction.
