153077-87-3Relevant articles and documents
Identification and synthesis of macrolide pheromones of the grain beetle oryzaephilus surinamensis and the frog spinomantis aglavei
Hoetling, Susann,Haberlag, Birte,Tamm, Matthias,Collatz, Jana,Mack, Patrick,Steidle, Johannes L. M.,Vences, Miguel,Schulz, Stefan
supporting information, p. 3183 - 3191 (2014/03/21)
Macrolide lactones, the so called cucujolides derived from unsaturated fatty acids, are aggregation pheromones of cucujid grain beetles. Thirty years ago, Oehlschlarger etaal. showed that (3Z,6Z)-dodeca-3,6-dien-11-olide (4) and the respective 12-olide (7) attract the sawtoothed grain beetle Oryzaephilus surinamensis, whereas (5Z,8Z,13R)-tetradeca-5,8-dien-13-olide (5) increases the response synergistically. The frass of this beetle is attractive for its parasitoid Cephalonomia tarsalis, which potentially can be used for pest control. A GC/MS analysis of attractive frass showed the presence of 5, together with an unknown isomer. CucujolideaV was tentatively identified also in the femoral glands, pheromone-releasing structures, of the Madagascan mantelline frog Spinomantis aglavei. Therefore, a new route to synthesize doubly unsaturated macrolides allowing the flexible attachment of the side chain was developed. A straightforward method to obtain Zaconfigured macrolides involves ring-closing alkyne metathesis (RCAM) followed by Lindlar-catalyzed hydrogenation. This methodology was extended to homoconjugated diene macrolides by using RCAM after introduction of one Zaconfigured double bond in the precursor by Wittig reaction. A tungsten benzylidyne complex was used as the catalyst in the RCAM reaction, which afforded the products in high yield at room temperature. With the synthetic material at hand, the unknown isomer was identified as the new natural product (5Z,8Z,12R)-tetradeca-5,8-dien-12-olide, cucujolideaX (8). Furthermore, the route also allowed the synthesis of cucujolideaV in good yield. The natural products were identified by the synthesis of enantiomerically pure or enriched material and gas chromatography on chiral phases. The new macrolide (R)-8 proved to be biologically active, attracting female O.asurinamensis, but no males. The synthetic material allowed the identification of (R)-5 in both the beetle and the frog. Attractive synthesis: Females of the sawtoothed grain beetle Oryzaephilus surinamensis are attracted to the new macrolide (5Z,8Z,12R)-tetradeca-5,8-dien-12-olide, cucujolideaX, prepared by using a combination of Wittig reaction and ring-closing alkyne metathesis (RCAM; see scheme). The synthetic approach also allows the synthesis of the similar cucujolideaV, used by both the beetle and the mantellid frog Spinomantis aglavei.
Asymmetric amplification by kinetic resolution using a racemic reagent: Example in amine acetylation
Satyanarayana, Tummanapalli,Kagan, Henri B.
, p. 5785 - 5789 (2008/03/28)
The reaction of a racemic reagent on a mixture of enantiomers with small ee (ee = enantiomeric excess) has been studied for amine acylation. A substantial asymmetric amplification could be- realized, for example, from 67 to > 95.5 ee. The combination of asymmetric amplifications is subsequently discussed. Two sequential asymmetric amplifications, one using a racemic reagent and another using a positive nonlinear effect allowed us to start from 1.5 % ee and end with a large amount of a product of 97% ee.
Catalytic enantioselective cyclopropanation with bis(halomethyl) zinc reagents. II. The effect of promoter structure on selectivity
Denmark, Scott E.,Christenson, Beritte L.,O'Connor, Stephen P.
, p. 2219 - 2222 (2007/10/02)
The catalytic, enantioselective cyclopropanation of cinnamyl alcohol has been accomplished with bis (iodomethyl)zinc in the presence of chiral bis(sulfonamides) derived from cyclohexanediamine. An extensive survey of diamine and sulfonamide structure has revealed a marked sensitivity to the spatial relationship of the amine groups, but only a modest dependence on the sulfonamide residue.
Catalytic Asymmetric Addition of Polyfunctional Dialkylzincs to β-Stannylated and β-Silylated Unsaturated Aldehydes
Ostwald, Roswitha,Chavant, Pierre-Yves,Stadtmueller, Heinz,Knochel, Paul
, p. 4143 - 4153 (2007/10/02)
The addition of functionalized dialkylzincs to readily available β-stannylated or β-silylated unsaturated aldehydes in the presence of a catalytic amount of (1R,2R)-1,2-bis(trifluorosulfonamido)cyclohexane (8 mol percent) provides chiral allylic alcohols
A Catalytic Enantioselective Reaction Using a C2-Symmetric Disulfonamide as a Chiral Ligand: Alkylation of Aldehydes Catalyzed by Disulfonamide-Ti(O-i-Pr)4-Dialkyl Zinc System
Takahashi, Hideyo,Kawakita, Takashi,Ohno, Masaji,Yoshioka, Masato,Kobayashi, Susumu
, p. 5691 - 5700 (2007/10/02)
Excellent enantioselective alkylation of aldehydes with dialkylzinc has been developed.This methodology is based on the concept of modifying the Lewis acid with a C2-symmetric, electron-withdrawing disulfonamide.The chiral Lewis acid catalysts used in the present study are the titanium complexes, prepared in-situ from disulfonamide and Ti(O-i-Pr)4.Key Words: Chiral disulfonamide; chiral titanium complex; enantioselective alkylation; dialkyl zinc; catalytic reaction
