A convenient preparaton ofγ-lactones and dialkyltetrahydrofurans from the reaction of fatty acids with epoxides using lithium naphthalenide

Fatty acids reacted with epoxides using lithium naphthalenide in the presence of diethylamine to give corresponding 4-hydroxy acids. These 4-hydroxy acids easily tended to cyclize into their correspondingγ-lactones by refluxing in benzene. Reduction of theseγ-lactones with lithium aluminum hydride followed by intramolecular dehydration with potassium bisulfate afforded corresponding dialkyl tetrahydrofuran derivatives in high yields. For example, 4-methyl-2-(8-nonenyl)γ-butyrolactone (III) was obtained from 10-undecylenic acid and propylene oxide. 2-Methyl-4-(8-nonenyl) tetrahydrofuran (IV) was produced from (III). 2-Methyl-4-(8-nonenyl) and 2-ethyl-4-(8-nonenyl) tetrahydrofurans are woody smelling and may be used as perfumery materials.     

Mammalian Exocrine Secretions. XII: Constituents of Interdigital Secretions of Bontebok, Damaliscus dorcas dorcas, and Blesbok, D. d. phillipsi

In addition to the nine compounds identified in the interdigital secretion of the bontebok, Damaliscus dorcas dorcas, in a previous study, 76 compounds belonging to different compound types, were identified in the interdigital secretions of the bontebok and the blesbok, D. d. phillipsi. These compounds include alkanes, alcohols, aldehydes, ketones, fatty acids, terpenoids, -lactones, an isopropyl ester, long-chain hydroxyesters, 2-substituted pyridines, phenols, steroids, and dimethylsulfone. No qualitative differences were found between secretions from the two sexes or from animals from different habitats. Although no attempt was made to correlate territorial behavior or other behavioral phenomena with the qualitative composition of interdigital secretions from individual animals, available information seems to indicate that quantitative differences probably do not have a major semiochemical function. Only two species of bacteria, Bacillus brevis and Planococcus citreus, were found in the interdigital pouches of male and female members of the two subspecies, regardless of the habitat of the animals. B. brevis synthesized, among other unidentified constituents, (Z)-3-penten-2-ol, 2-hexanone, 2-octanone, 2-nonanone, tetradecanoic acid, pentadecanoic acid, heptadecanoic acid, octadecanoic acid, (Z)-9-hexadecenoic acid, and isopropyl hexadecanoate in vitro, while P. citreus produced, among others, the -lactones dodecan-4-olide and (Z)-6-dodecen-4-olide, which is one of the major constituents of the interdigital secretions of both subspecies. Some components of the interdigital secretions are not present in the interdigital glandular tissue, and the possibility is discused that these compounds could be produced by microbiological activity in the interdigital pouch.     

New Sphingolipids with a Previously Unreported 9-Methyl-C<Subscript>20</Subscript>-sphingosine Moiety from a Marine Algous Endophytic Fungus <Emphasis Type="Italic">Aspergillus niger</Emphasis> EN-13

Asperamides A (1) and B (2), a sphingolipid and their corresponding glycosphingolipid possessing a hitherto unreported 9-methyl-C₂₀-sphingosine moiety, were characterized from the culture extract of Aspergillus niger EN-13, an endophytic fungus isolated from marine brown alga Colpomenia sinuosa. The structures were elucidated by spectroscopic and chemical methods as (2S,2′R,3R,3′E,4E,8E)-N-(2′-hydroxy-3′-hexadecenoyl)-9-methyl-4,8-icosadien-1,3-diol (1) and 1-O-β-d-glucopyranosyl-(2S,2′R,3R,3′E,4E,8E)-N-(2′-hydroxy-3′-hexadecenoyl)-9-methyl-4,8-icosadien-1,3-diol (2). In the antifungal assay, asperamide A (1) displayed moderate activity against Candida albicans.     

The rate of ring opening of γ-and δ-lactones derived from meadowfoam fatty acids

δ-Lactones derived from meadowfoam (Limnanthes) fatty acids were reacted with amine and alcohol nucleophiles in a second-order reaction to provide the acyclic 5-hydroxy eicosanoic acid esters and amides. The rate of reaction for the ring opening of δ-lactones was compared to the rate of ring opening of γ-lactones and the rate of derivatization of meadowfoam fatty acids. δ-Lactones showed a much larger rate for the formation of derivatives than the corresponding γ-lactones or fatty acids. γ-Lactone had a rate constant >7700 times larger for the formation of butyl ester than meadowfoam fatty acids. The formation of amides from δ-lactones is even faster than the esterification reaction and requires no catalyst or solvent when conducted at the melting point of the lactone.     

Mammalian exocrine secretions: X. constituents of preorbital secretion of grysbok,Raphicerus melanotis

Using electron impact and chemical ionization mass spectrometry with methane and nitric oxide as reactant gases in conjunction with mass spectral analysis of the dimethyl disulfide derivatives of unsaturated constituents, 51 compounds have been identified in addition to the compounds previously found in the preorbital secretion of the grysbokRaphicerus melanotis. The compounds identified are saturated, monounsaturated, and diunsaturated alcohols and formates, saturated and monounsaturated aldehydes, saturated carboxylic acids,- and-lactones, alkyl methyl sulfides, and-hydroxyalkyl acetates. All of these compounds have unbranched structures. The constituent previously incorrectly identified as (Z)-5-tetradecen-1-ol, was found to consist of the coeluting (Z)-7- and (Z)-8-tetradecenols.     

Squash leaf glandular trichome volatiles: Identification and influence on behavior of female pickleworm moth [Diaphania nitidalis (Stoll.)] (Lepidoptera: Pyralidae)

Fourteen volatile compounds occurring in leaf trichomes of yellow squash (Cucurbita pepo L. cv. Early Prolific Straightneck) were identified. These compounds accounted for 83.5% of the volatile matrix. Ubiquitous constituents of the epidermis (myristic, palmitic, and stearic acids,n-tricosane, andn-pentacosane) accounted for 73.7%; these compounds were not bioassayed. The volatileso-,m-, andp-xylene, toluene, 2-heptanone, (R)-(+)- and (S)-(–)-limonene, and germacrene D were tested for their influence on attraction and oviposition by the pickleworm moth (Diaphania nitidalis Stoll.). No single compound, except germacrene D, was attractive. (R)-(+)-Limonene and 2-heptanone were weakly repellent. Mixtures of the highly volatile fractions were as attractive as volatiles emanating from whole, intact leaves. Oviposition levels on treated artificial sites corresponded with levels of visitation. Oviposition was significantly stimulated by whole-leaf volatiles, and (S)-(–)-limonene caused a slight but significant reduction.Mention of a trade name or proprietary product does not constitute a warranty or guarantee by the U.S. Department of Agriculture, nor does it imply exclusion of other products that may also be suitable.     

Identification and Synthesis of the Sex Pheromone of the Madeira Mealybug, <Emphasis Type="Italic">Phenacoccus Madeirensis</Emphasis> Green

Two components were identified from aeration extracts of the virgin female Madeira mealybug, Phenacoccus madeirensis as trans-(1R,3R)-chrysanthemyl (R)-2-methylbutanoate and (R)-lavandulyl (R)-2-methylbutanoate (with a ratio of 3:1) by a combination of gas chromatography retention time matches, mass spectrometry, and microchemical tests. The structures and chirality of the compounds were confirmed by comparing with synthetic compounds. The synthetic trans-(1R,3R)-chrysanthemyl (R)-2-methylbutanoate was highly attractive to males in laboratory bioassays; the synthetic (R)-lavandulyl (R)-2-methylbutanoate was weakly attractive. No synergistic effect was observed when the mixture of the two compounds was tested.     

Production and Predator-Induced Release of Volatile Chemicals by the Plant Bug Lygus hesperus

Both sexes of adult western tarnished plant bug, Lygus hesperus Knight (Heteroptera: Miridae), released three volatile chemicals in relatively large amounts when attacked by ants (Pogonomyrmex rugosus and Solenopsis xyloni) or when grabbed by forceps, as determined by solid-phase microextraction (SPME) and gas chromatography–mass spectrometry (GC–MS). The relative amounts of the volatile compounds, hexyl butyrate, (E)-4-oxo-2-hexenal, and (E)-2-hexenyl butyrate, absorbed by SPME as a percentage of the largest were 100%, 44%, and 4%, respectively, from females, and 83%, 37%, and 3% from males. Both ant species were repelled by the defensive discharges (confirmed by SPME) when the ants attacked L. hesperus adults. Sexually mature L. hesperus were individually extracted in pentane to quantify the mean amounts of hexyl butyrate (14.9 μg/female; 10.3 μg/male), (E)-4-oxo-2-hexenal (2.7 μg/female; 3.1 μg/male), and (E)-2-hexenyl butyrate (1.2 μg/female; 0.6 μg/male). (E)-4-Oxo-2-hexenal was unstable in solvent when in contact with a macerated adult, but relatively stable when the solution was decanted within minutes. The production of the three major volatile components began soon after the emergence of the adult and amounts increased for about 5–10 d with little or no increase thereafter. Minor additional constituents were cross-correlated in many cases with the three major ones. A cost of defensive secretion is suggested for females but not for males, because heavier females produced more volatile compounds than lighter females. The initial discharge percentage, defined as the proportion of volatile compounds initially present that is discharged to defend against predation was estimated at about 50% in males and 70% in females. Newly eclosed adults did not produce volatile chemicals until 2 d after molting.     

New 17-Methyl-13-Octadecenoic and 3,16-Docosadienoic Acids from the Sponge <Emphasis Type="Italic">Polymastia penicillus</Emphasis>

The phospholipid fatty acid composition of the North-East Atlantic sponge Polymastia penicillus (South Brittany, France) was investigated. Sixty fatty acids (FA) were identified as methyl esters (FAME) and N-acyl pyrrolidides (NAP) by gas chromatography–mass spectrometry (GC/MS), including eight Δ5,9 unsaturated FA and three long-chain 2-hydroxylated FA. The major phospholipid FA were palmitic (14.3% of the total FA mixture), vaccenic (12.7%), 15(Z)-docosenoic (13.4%) and 5(Z),9(Z)-hexacosadienoic (13.3%) acids. In addition to the iso- and anteiso-branched saturated FA, several unusual short-chain branched saturated FA were identified. In addition to the known Δ5,9 FA, and interestingly regarding their identification by GC–MS as N-acyl pyrrolidides, was the co-occurrence of unusual FA possessing a Δ3, Δ4 and Δ5 double bond such as iso-4-pentadecenoic, iso-5-heptadecenoic, anteiso-5-heptadecenoic and two new compounds, not hitherto found in nature, namely 17-methyl-13-octadecenoic (0.8%) and 3,16-docosadienoic (1.1%) acids.     

Comparison of Urinary Scents of Two Related Mouse Species, <Emphasis Type="Italic">Mus spicilegus</Emphasis> and <Emphasis Type="Italic">Mus domesticus</Emphasis>

Whereas the house mouse (Mus domesticus) has been studied extensively in terms of physiology/behavior and pheromonal attributes, the evolutionarily related mound-building mouse (Mus spicilegus) has received attention only recently due to its divergent behavioral traits related to olfaction. To date, no chemical studies on urinary volatile compounds have been performed on M. spicilegus. The rationale for our investigations was to determine if there are differences in urinary volatiles of intact and castrated M. spicilegus males and to explore further whether this species could utilize the same or structurally similar pheromones as the male house mouse, M. domesticus. The use of capillary gas chromatography/mass spectrometry (GC-MS) together with sorptive stir bar extraction sampling enabled quantitative comparisons between the intact and castrated M. spicilegus urinary profiles. Additionally, through GC-MS and atomic emission (sulfur-selective) detection, we identified qualitative molecular differences between intact M. spicilegus and M. domesticus. A series of volatile and odoriferous lactones and the presence of coumarin were the unique features of M. spicilegus, as was the notable absence of 2-sec-butyl-4,5-dihydrothiazole (a prominent M. domesticus male pheromone) and other sulfur-containing compounds. Castration of M. spicilegus males eliminated several substances, including δ-hexalactone and γ-octalactone, and substantially decreased additional compounds, suggesting their possible role in chemical communication. Some other M. domesticus pheromone components were also found in M. spicilegus urine. These comparative chemical analyses support the notion of metabolic similarities as well as the uniqueness of some volatiles for M. spicilegus, which may have a distinct physiological function in reproduction and behavior.     

(2<Emphasis Type="Italic">S</Emphasis>,8<Emphasis Type="Italic">Z</Emphasis>)-2-Butyroxy-8-heptadecene: Major Component of the Sex Pheromone of Chrysanthemum Gall Midge, <Emphasis Type="Italic">Rhopalomyia longicauda</Emphasis>

The sex pheromone of the chrysanthemum gall midge, Rhopalomyia longicauda (Diptera: Cecidomyiidae), the most important insect pest in commercial plantations of chrysanthemum, Dendranthema morifolium (Ramat.) Tzvel., in China, was identified, synthesized, and field-tested. Volatile chemicals from virgin females and males were collected on Porapak in China and sent to the United Kingdom for analysis. Coupled gas chromatographic–electroantennographic detection (GC-EAG) analysis of volatile collections from females revealed two compounds that elicited responses from antennae of males. These compounds were not present in collections from males. The major EAG-active compound was identified as 2-butyroxy-8-heptadecene by gas chromatographic (GC) retention indices, mass spectra, in both electron impact and chemical ionization modes, hydrogenation, epoxidation, and derivatization with dimethyldisulfide. The lesser EAG-active compound was identified as the corresponding alcohol. The ratio of butyrate to alcohol in the collections was 1:0.26. Racemic (Z)-8-heptadecen-2-ol and the corresponding butyrate ester were synthesized from (Z)-7-hexadecenyl acetate, and the synthetic compounds found to have identical GC retention indices and mass spectra to those of the natural, female-specific components. Analysis of the volatile collections on an enantioselective cyclodextrin GC column showed the natural pheromone contained (2S,8Z)-2-butyroxy-8-heptadecene. Field tests showed that rubber septa containing racemic (Z)-2-butyroxy-8-heptadecene were attractive to R. longicauda males. The (naturally occurring) S-enantiomer was equally as attractive as the racemate, while the R-enantiomer was not attractive to males, and did not inhibit the activity of the S-enantiomer. The attractiveness of the butyrate was significantly reduced by the presence of even small amounts of the corresponding alcohol.     

Reaction of γ-Tocopherol with Hypochlorous Acid

In addition to being a very good antioxidant, γ-tocopherol is also an excellent electrophile trap. This is a study of the reactivity of γ-tocopherol with hypochlorous acid/hypochlorite, a potential biological foe that is both an oxidant and an electrophile. Aqueous sodium hypochlorite (1.72 mmol; pH 7.4) was stirred with γ-tocopherol (0.12 mmol) in hexane for 2 min at room temperature. The following products were isolated: γ-tocopheryl quinone (0.6%), tocored (10%), 3-chloro-γ-tocopheryl quinone (14%), an ether dimer of 3-chloro-γ-tocopheryl quinone (0.4%), two isomers of 5-(5-γ-tocopheryl)-γ-tocopherol (3 and 2% respectively), 5-chloro-γ-tocopherol (14%) and two chlorinated dimers (14 and 24% respectively) which were identified as diastereomers of (3R,10R)-11a-chloro-2,3,9,10-tetrahydro-3,5,6,10,12,13-hexamethyl-3,10-bis[(4R,8R)-4,8,12-trimethyltridecyl]-1H-pyrano(3,2a)-8H-pyrano(3,2g)-dibenzofuran-14(7aH)(14aH)-one. The chlorinated dimers, 5-chloro-γ-tocopherol, 3-chloro-γ-tocopheryl quinone and its ether dimer are new compounds.     

Urinary volatile profiles of pine vole,Microtus pinetorum,and their endocrine dependency

The volatile compounds identified by combined gas chromatography-mass spectrometry inMicrotus pinetorum urine include alcohols, aldehydes, hydrocarbons, ketones, nitriles, and pyrazines. Several lactone derivatives were found to be characteristic urinary substances of this species. Ovariectomy depressed concentrations of only five out of a great number of profile constituents. Elevating estrogen levels (by exposing females to male-soiled bedding or treating them with estradiol) tends to depress the urinary concentration of a number of selected volatiles. Estrogen implantation provoked a periodic increase in the level of three compounds (nonanal, benzal-dehyde, and an unidentified substance). The volatile profile of castrate male urine was similar to that of intact male urine. Female urine contained -octanoic lactone and two pyrazine derivatives in higher concentrations andp-methyI-propenylbenzene in a lower concentration, when compared to male urine. No qualitative differences between the urinary profiles of males and females were observed.     

Male-Produced Aggregation Pheromones of the Cerambycid Beetles <Emphasis Type="Italic">Xylotrechus colonus</Emphasis> and <Emphasis Type="Italic">Sarosesthes fulminans</Emphasis>

Adults of both sexes of the cerambycid beetles Xylotrechus colonus (F.) and Sarosesthes fulminans (F.) were attracted to odors produced by male conspecifics in olfactometer bioassays. Analyses of headspace volatiles from adults revealed that male X. colonus produced a blend of (R)- and (S)-3-hydroxyhexan-2-one and (2 S,3 S)- and (2R,3R)-2,3-hexanediol, whereas male S. fulminans produced (R)-3-hydroxyhexan-2-one and (2 S,3R)-2,3-hexanediol. All of these compounds were absent in the headspace of females. Two field bioassays were conducted to confirm the biological activity of the synthesized pheromones: (1) enantiomerically enriched pheromone components were tested singly and in species-specific blends and (2) four-component mixture of racemic 3-hydroxyhexan-2-one plus racemic 2-hydroxyhexan-3-one and the four-component blend of the stereoisomers of 2,3-hexanediols were tested separately and as a combined eight-component blend. In these experiments, adult male and female X. colonus were captured in greatest numbers in traps baited with the reconstructed blend of components produced by males, although significant numbers were also captured in traps baited with (R)-3-hydroxyhexan-2-one alone or in blends with other compounds. Too few adult S. fulminans were captured for a statistical comparison among treatments, but all were caught in traps baited with lures containing (R)-3-hydroxyhexan-2-one. In addition to these two species, adults of two other species of cerambycid beetles, for which pheromones had previously been identified, were caught: Neoclytus a. acuminatus (F.) and its congener Neoclytus m. mucronatus (F.). Cross-attraction of beetles to pheromone blends of other species, and to individual pheromone components that are shared by two or more sympatric species, may facilitate location of larval hosts by species that compete for the same host species.     

Stereospecific metabolism of isomeric epoxyoctadecanoic acids in the lactone-producing yeast Sporidiobolus salmonicolor

The metabolic course of four isomeric epoxyfatty acids derived from oleic-, elaidic-, (Z)-, and (E)-vaccenic acids in the lactone-producing yeast, Sporidiobolus salmonicolor, was studied by using the deuterium-labeled precursors. Dihydroxy-, hydroxyoxo-, and hydroxy fatty acids as well as γ-lactones were identified as metabolic intermediates. Quantitative analysis of the label content and estimation of the enantiomeric composition of the lactones established that, in the first step, the racemic epoxyfatty acids were enantiospecifically hydrolyzed by an epoxide hydrolase. During the subsequent metabolism, the stereochemical orientation of the hydroxy groups of the dihydroxyfatty acids were modified by an oxidation/reduction step.     

Feeding responses of snowshoe hares (Lepus americanus) to volatile constituents of red fox (Vulpes vulpes) urine

This study investigated the influence of the volatile constituents of red fox (Vulpes vulpes) urine in suppressing feeding by snowshoe hares (Lepus americanus) on coniferous tree seedlings. Pen and field bioassays indicated that the odor of fox urine and its principal component, 3-methyl-3-butenyl methyl sulfide, had a negative effect on feeding behavior of hares. The other sulfur-containing compounds, 2-phenylethyl methyl sulfide and 3-methylbutyl methyl sulfide, as well as six other constituents, were not effective. Synthetic urine mixtures composed of eight and nine volatile constituents, respectively, did not suppress feeding in pen bioassays. However, the mixture of eight compounds in a field bioassay did result in significantly fewer seedlings being eaten by hares than in the control. 3-Methyl-3-butenyl methyl sulfide may act as an interspecific chemical signal which induces a fear or avoidance response in hares. Additional work is required to determine the optimum concentration and release system for 3-methyl-3-butenyl methyl sulfide to be used as a mammalian semiochemical in crop protection.     

Highly selective asymmetric synthesis of 2-hydroxy fatty acid methyl esters through chiral oxazolidinone carboximides

Highly selective asymmetric synthesis of 2-hydroxy fatty acid methyl esters has been accomplioshed through chiral imide enolates. Five chiral oleic acid imides were prepared by reaction of oleioc acid with pivaloyl chloride followed by reaction with five different lithiated chiral oxazolidinones including (R)-(+)-4-benzyl-2-, (S)-(-)-4-benzyl-2-, (4R,5S)-(+)-4-methyl-5-phenyl-2-, (4S,5R)-(-)-4-methyl-5-phenyl-2-, and (R)-(+)-4-isopropyl-2-oxazolidinones in 88–92% yileds. The chiral imides were reacted with NaN(Me₃Si)₂ at −78°C to give enolates, which subsequently reacted with 2-(phenylsulfonyl)-3-phenyloxaziridine to give hydroxylated products in 78–83% yields. Methanolysis of the hydroxylated products with magnesium methoxide gave methyl 2-hydroxyoleate. Enantiomeric excesses (ee) of the products were determined to be very high (98–99% ee) by ¹H nuclear magnetic resonance study after esterification of the hydroxy group with (S)-(+)-O-acetylmandelic acid. Enantioselective hydroxylation of other fatty acids including elaidic, petroselinic, vaccenic, and linoleic was evaluated under the similar conditions using (4R, 5S)-(+)-4-methyl-5-phenyl-2-oxazolidinone as a chiral auxiliary to give 98% ee values for all cases.     

Identification of Male-Produced Aggregation Pheromone of the Curculionid Beetle <Emphasis Type="Italic">Sternechus subsignatus</Emphasis>

Analyses of the headspace volatiles produced by males and females of Sternechus subsignatus Boheman (Coleoptera: Curculionidae) revealed seven male-specific compounds. The major component was (E)-2-(3,3-dimethylcyclohexylidene)-ethanol, and the minor components were 1-(2′-hydroxyethyl)-1-methyl-2-isopropenylcyclobutane (grandisol), 7-methyl-3-methyleneoct-6-en-1-ol, (Z)-2-(3,3-dimethylcyclohexylidene)-ethanol, (Z)- and (E)-2-(3,3-dimethylcyclohexylidene)-acetaldehyde, and (E)-2-(3,3-dimethylcyclohexylidene) acetic acid. The latter compound is described for the first time as a natural product. Only four of the seven identified compounds showed electrophysiological activity. Enantioselective gas chromatography showed that the natural grandisol is the (1R,2S)-stereoisomer. The major component, (E)-2-(3,3-dimethylcyclohexylidene)-ethanol, attracted S. subsignatus in olfactometer bioassays. Studies are in progress to evaluate the biological activity of the major component and the EAD-active mixture under field conditions.     

Mammalian Exocrine Secretions XI. Constituents of the Preorbital Secretion of Klipspringer, Oreotragus oreotragus

The ketones 3-pentanone, 4-methyl-2-pentanone, 5-methyl-3-hexanone, 4-methyl-3-hexanone, and the esters ethyl propanoate, 2-methylpropyl acetate, ethyl 3-methylbutanoate, and 2-methylpropyl propanoate were identified as the only volatile organic constituents of the preorbital secretion of the klipspringer, Oreotragus oreotragus. These compounds are considerably more volatile than those found in the preorbital secretions of other antelopes belonging to the tribe Antelopini. More than 50% of the preorbital secretion consists of proteinaceous material, which probably acts as a controlled-release substance in retarding the evaporation of the volatile constituents of the secretion from territorial marks.     

Identification of Novel α-Methoxylated Phospholipid Fatty Acids in the Caribbean Sponge <Emphasis Type="Italic">Erylus goffrilleri</Emphasis>

The phospholipid fatty acid composition of the Caribbean sponge Erylus goffrilleri is described for the first time. A total of 70 fatty acids with chain lengths between 13 and 29 carbons were identified in the sponge. Methyl-branched fatty acids predominated in E. goffrilleri suggesting the presence of a considerable number of bacterial symbionts. The novel fatty acids (5Z,9Z)-2-methoxy-5,9-hexadecadienoic acid, (5Z,9Z)-2-methoxy-5,9-octadecadienoic acid, (5Z,9Z)-2-methoxy-5,9-nonadecadienoic acid, and (5Z,9Z)-2-methoxy-5,9-eicosadienoic acid are described for the first time in the literature. In addition, the iso-methyl-branched fatty acids (9Z)-2-methoxy-15-methyl-9-hexadecenoic acid and (5Z,9Z)-2-methoxy-15-methyl-5,9-hexadecadienoic acid, also identified in E. goffrilleri, were identified for the first time in nature. Based on the identified metabolites it is proposed that the unprecedented biosynthetic sequence: i-17:1Δ9 → 2-OMe-i-17:1Δ9 → 2-OMe-i-17:2Δ5,9 might be responsible for the biosynthesis of the novel iso-α-methoxylated fatty acids in E. goffrilleri.