63557-55-1Relevant academic research and scientific papers
High-performance liquid chromatography/thermospray mass spectrometry of some prostaglandins of time F series
Abian,Gelpi
, p. 608 - 616 (2007/10/02)
Thermospray (TSP) mass-spectra and chromatographic characteristics of the prostanoids PGF(2α), 6-keto-PGF(1α), 2,3-dinor-6-keto-PGF(1α) and their methyl esters and methoximes are reported. The spectra of these compounds are dominated by ions of the type [M + H + xNH3 - nH2O]+ in the positive-ion mode and [M - H + xAcOH - nH2O]- in the negative-ion mode (n ranges from 0-4 and x is 0 or 1). The relative abundances of these ions depend on the particular structure, source and interface temperatures and eluent composition. In addition, these compounds show losses of 44 mass units, mainly due to the lass of the C-10-C-11 moiety, as demonstrated by deuterium labelling of PGF(2α). Methoximated derivatives of 6-keto-PGF(1α) also show low-abundance ions due to fragmentation in the position α to the methoxime group. The liquid-phase equilibria of tautomers of 2,3-diner-6-keto-PGF(1α) or products thereof which direct-its particular chromatographic behavior, can be effectively blocked by methoximation of the keto group thus improving its detectability. Detection limits of 20 ng on-column may be obtained for this derivative. Adsorption and hydrolysis in the interface are the principal factors responsible for this relatively high detection limit.
Nitro-Olefin Trapping Reactions of Enolates In Situ Generated by Conjugate Addition Reaction: Short Syntheses of PGE1, 6-Oxo-PGE1, 6-Oxo-PGF1α, and PGI2
Tanaka, Toshio,Hazato, Atsuo,Bannai, Kiyoshi,Okamura, Noriaki,Sugiura, Satoshi,et al.
, p. 813 - 824 (2007/10/02)
The nitro-olefin trapping of the enolates in situ generated by conjugate addition of organocopper reagents to the chiral oxygenated cyclopentenone synthon, R-4, gives the three-component coupling products in a regiospecific manner.The intermediary nitronate anion 17 is further transformed into the nitro compound or 6-oxo-PGE1 (19) in a single pot.This coupling reaction is applicable to syntheses of naturally occurring prostaglandins such as PGE1, 6-oxo-PGF1α, and PGI2.
A FACILE SYNTHESIS OF 6-OXO-PGF1α AND 6-OXO-PGE1
Nokami, Junzo,Ono, Toshio,Hiraga, Junji,Wakabayashi, Shoji
, p. 557 - 560 (2007/10/02)
6-Oxo-PGF1α and 6-oxo-PGE1 were synthesized from 7-t-butyl-dimethylsililoxy-6--2-oxabicyclooctan-2-one (1) and 7-tetrahydropyranyloxy-6--2-oxabic
Synthesis of (5E)- and (5Z)-11-Deoxy-6,11α-epoxy-Δ5-prostaglandin F1α Sodium Salts: 6,11α-Enol Ether Isomers of Prostacyclin
Sih, John C.,Graber, David R.
, p. 4919 - 4927 (2007/10/02)
The key intermediates, (5S,6R)- and (5R,6R)-11-deoxy-6,11α-epoxy-5-hydroxy cyclic ethers, 22a,b, were prepared from the reaction of a C-9 silyl PGF2α derivative 12 with mercuric acetate (oxymercuration), followed by conversion of the mercurioacetate substituent to a hydroxy group.Attempts to construct the 6,11α oxygen bridge by reaction of 12 and other C-9 protected PGF2α derivatives with iodine, N-bromosuccinimide, and phenylselenenyl chloride were unsuccessful.Reaction of 11 and 12 with iodine resulted in removal of the C-9 blocking group and the isolation of 6,9-iodo cyclic ether products.Treatment of 13 with phenylselenenyl chloride gave the β-chlorophenylselenenyl addition adduct 18.Conversion of alcohols 22a,b to their mesylate derivatives, 25a,b, and subsequent reaction with potassium methoxide in dimethyl sulfoxide afforded the labile Δ5 enol ethers, 29a,b.The success of this elimination reaction was critically dependent on the base, the reaction solvent, and the workup conditions.The structural assignments of 29a,b were based on their spectral properties and hydrolysis to 6-keto-PGF1α methyl ester.The stereoconfiguration at C-6 was assigned by conversion of the oxymercuration product obtained from 12 to the 5,6-dihydro-6,11α-cyclic ether 20.The C-5 stereoconfiguration of alcohols 22a,b was established by the mode of formation of enol ethers 29a,b.In contrast to PGI2 methyl ester, 29a,b in aqueous acid showed a greater tendency to form the internal ketal 34 during hydrolysis to 6-keto-PGF1α methyl ester.
