The structure elucidations of new fungal products CP-225,917 and CP-263,114 are described. The structures, including relative stereochemistry, were established using a variety of analytical data and extensive NMR analysis. The compounds possess a bicyclo[4.3.1]deca-1,6-dien-10-one system in conjunction with a maleic anhydride moiety, a γ-lactol, and two alkenyl side chains. They are related to nonadrides, and their biosynthetic origins are proposed. The producing organism also yields zaragozic acid A, and both zaragozic acids and compounds CP-225,917 and CP-263,114 appear to be derived from the condensation of oxaloacetic acid and the corresponding monocarboxylic acid.
matography on a silicone column at 160" showed no detectable amount of i m p~r i t i e s .~~The second sample of CDaCOOH was prepared by carbonation of the Grignard reagent prepared from 5 g. of CDaBr (Merck, Canada; 9970 deuterated) and 2.5 g. of crystalline magnesium in 45 ml. of dried ether. After hydrolysis with the minimum amount of 25YG sulfuric acid, the ether solution was decanted and combined with subsequent ether washings of the magnesium salts. The ether was distilled and the acetic-& acid was fractionated; a middle cut was used for the acidity measurements.Pivalic-dg Acid.-Carbon dioxide was passed over a cooled and stirred solution of the Grignard reagent prepared from 5 g. of &butyl-& chloride (Merck of Canada) and 1.34 g. of crystalline magnesium. After hydrolysis with dilute sulfuric acid, the washed and dried ether solution was distilled 5iving 1.7 g. of pivalic-dg acid in two fractions, b.p. 160-165 . The second fraction was stored in a sublimer and a small amount was sublimed as required for the conductivity measurements.Calcd. for CsDgH02: D, 90 atom %. Found: D, 86 atom %.Ordinary pivalic acid was prepared in the same manner from freshly distilled t-butyl chloride. It gave the same results as commercial pivalic acid.Benzoic Acids.-Reagent grade benzoic acid was sublimed immediately before use in the conductivity measurements.Deuterium chloride, prepared from DzO and benzoyl chloride, 34Halevi (ref. lob) reports t h a t his sample of Merck C D C O O D contained traces of several contaminants. (33) Analysis of the Microanalytical Laboratory of t h e University of California. T h e deuterium analyses were by density measurement of the combustion water by a drop suspension method. At t h e time of this work, this method was not accurate for high deuterium content and tended t o give low results, T h e analyses were used only as supplemental evidence for substantial deuterium content of our samples.was passed through successive portions of a 1 mole yo solution of sublimed gallium bromide in benzene until density measurements indicated an isotopic purity of >957c.36 The highest value found for the density of our benzene-& is dZ52& 0.9438, lit.35 dZ5z5 0.9461.A sample having dZ625 0.940 was brominated with bromine and iron yielding bromobenzene-d5, b.p. 153-155", nZ6D 1.5564.AnaZ.33 Calcd. for CeDsBr: D, 100 atom o/c. Found: D , 90 atom %.The bromide was converted to the Grignard reagent and carbonated in the usual way. The product benzoic-& acid, m.p. 122-123', was crystallized from water and was sublimed Immediately before use.Calcd. for C7D5H02: D, 83 atom %. Found: D , 75 atom 76.Benzoic-2,6-& acid was prepared in a similar manner from bromoben~ene-2,6-d*.~~ The product was also crystallized from water and sublimed; m.p. 122.0-122.6".Calcd. for C7D2H402: D , 33 atom %. Found: D, 30 atom %.Conductivity Measurements.-Solutions were made up using distilled water which had been passed through a Penfield mixedbed demineralizer, model M-8, and aliquots were titrated with standardized sodium hydroxide....
7183careful electronic integration of the vinyl proton portion of the nmr afforded an accurate determination of the absolute amounts of the trans,trans-and cis,rruns-2,3-diphenyl-l-(cr-styryl)cyclopropane stereoisomers present. The entire sample was then subjected to reversed-phase polystyrene bead liquid-liquid chromatography (uide supra). The two cyclopropane isomers were collected as one peak and again subjected to nmr analysis. Collection and analysis of separate fractions allowed nearly complete separation; however, the analytical results proved more simply obtained by direct assay of the one combined chromatographic peak. The 1,2,3,4-tetrahydro-1 ,Zmethano-l,3-diphenylnaphthalene photoproduct was isolated from the chromatogram and assayed by weight. Its mass accounted for the remainder of the photolysis sample. The nmr analysis was calibrated with known mixtures of the cyclopropane isomers.Specific data for individual irradiations are given below as follows: weight of hydrocarbon and additive (if any), filter system used, amount of light absorbed, quantum yield for the appearance of the cyclopropyl stereoisomer, mass of 1,2,3,4-tetrahydro-1 ,2-methano-l,3-diphenylnaphthalene isolated, quantum yield for the appearance of the methanonaphthalene, total conversion of starting material.Run QY-1. rrans,rrans-2,3-Diphenyl-l-(a-styryl)cyclopropane, 293 mg, no benzophenone, filter I, 9.13 mEinsteins, 0.058, 0.029, 62.6 mg of methanonaphthalene, 0.023,53 %.Run QY -2. trans,~rans-2,3-Diphenyl-l-(a-styryl)cyclopropane, 302 mg, no benzophenone, filter I, 3.72 mEinsteins, 0.052, 0.023, 25.0 mg of methanonaphthalene, 0.023,23 %.Run QY-3. cis,trans-2,3-Diphenyl-l-(a-styryl)cyclopropane, 298 mg, no benzophenone, filter I, 4.50 mEinsteins, less than 0.0067, less than 0.0067, no detectible methanonaphthalene, less than 3 %.Run QY-S1. rrans,t~ans-2,3-Diphenyl-l-(a-styryl)cyclopropane, 295 mg, 4.069 g of benzophenone, filter 11, 1.33 mEinsteins, 0.340, 0.340, no methanonaphthalene, 0,45 %.Run QY-S2. ~rans,rrans-2,3-Diphenyl-1-(a-styryl)cyclopropane, 299 mg, 2.989 g of benzophenone, filter 11, 0.710 mEinstein, 0.345,0.345, no methanonaphthalene, 0,25 %. nmr (CDC13) 7 2. 03-2.88 (m, 15 H, arom), 7.90 (s, 3 H, methyl); uv (ethanol) 234 nm max (E 52,000), 286 nm max (E 8000). Anal. Calcd for CZ3Hl8: C, 93.84; H, 6.16. Found: C, 93.96; H, 6.19.Direct Irradiation of cis,rrans-2,3-Diphenyl-l-(a-styryl)cyclopropane. A solution of 170 mg (0.574 mmol) of cis,rruns-2,3-diphenyl-1-(a-styry1)cyclopropane in 250.0 ml of purified cyclohexane was irradiated for 2.5 hr under deoxygenated nitrogen" through a Corex filter (A 2 260 nm) with a Hanovia 450-W medium-pressure mercury lamp in a quartz immersion well. Nmr spectra taken before and after irradiation showed that 50% of the starting material had disappeared and that roughly equal amounts of the truns,tru~zs-2,3-diphenyl-l-(a-styryl)cyclopropane and 1,2,3,4-tetrahydro-1 ,Zmethano-1,3-diphenylnaphthalene had appeared.Photolysis Apparatus for Quantum Yields. The "black box" irradiation appa...
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