Isolation of 2-Solanesyl-1,4-naphthoquinone from Streptococcus faecalis, 10 Cl

Inhomogeneity of vitamin K2 in Escherichia coli

“…As detailed in Methods, its ultraviolet spectrum, recorded in buffered ethanol, altered on treatment with sodium borohydride in the manner characteristic of quinones (Lester et al, 1964). Furthermore, when the spectrum was recorded in isooctane the chromophore was easily recognized as that of a 2-alkyl-l,4-naphthoquinone (Baum and Dolin, 1965).…”

“…To establish the generality of bacterial menaquinone inhomogeneity we are undertaking the detailed examination of the menaquinone content of organisms currently believed to produce but a single prenylog. The organism discussed herein, Escherichia coli, was known to form menaquinone-8 (I, n = 8) (Bishop et al, 1962) together with a 2-demethyl derivative, tentatively attributed structure II, n = 8 (Baum and Dolin, 1965) .…”

Peracid oxidation of tetramethylallene

“…4-Hydroxy-2,4-dimethylpent-l-en-3-one (7). A 25-ml portion of sec-collidine was added directly to 3.0 g of 2-bromo-4-hydroxy-2.4-dimethyl-3-pentanone and this mixture was refluxed for 2.5 hr.…”

“…The solvent was removed by flash evaporation to give 0.77 g of crude material. A pure sample of 316 was collected by preparative glpc: ir 5.76, 5.82, and 8.00 µ; nmr 7.10 (septet, 1,7=7 Hz), 7.99 (s, 3), 8.57 (s, 6), and 8.98 (d, 6,7= 7 Hz).…”

“…The relative proportions of these materials was subject to change with variation in the experimental parameters, but in a typical example the following was observed: 52% 3, 39 % 4, 3 % 5, 2 % 6, and 4% 7. Acetoxy ketone 3 was prepared by lead tetraacetate oxidation10 of diisopropyl ketone; hydroxy acetoxy ketone 4 was secured by semiacetylation of dihydroxy diisopropyl ketone; and a bromination-dehydrobromination sequence led to conjugated ketone 7 from hydroxy diisopropyl ketone.…”