The scent gland composition of the Mangshan pit viper, Protobothrops mangshanensis

• Jonas Holste,
• Paul Weldon,
• Donald Boyer and
• Stefan Schulz

Beilstein J. Org. Chem. 2024, 20, 2644–2654, doi:10.3762/bjoc.20.222

• various lipid classes including sterols, triacylglycerols, and common fatty acid methyl esters [15]. Mass spectrometric analysis of the lipid content of crotalines, mainly the Western Diamondback Rattlesnake (C. atrox), confirmed the presence of cholesterol [3][6][11][16], fatty acids [11], fatty amides

• gap between m/z 192 and 232 indicates a methyl group either at either C-5 or C-6. Taken together, the data from the derivatizations led to the conclusion that one methyl group is located at C-4 and a second at C-6. This is consistent with regular fatty acid biosynthesis of mid-chain methyl

• formation requires a finely tuned biosynthetic machinery that deviates from the common fatty acid biosynthetic pathway operating, also in snakes, that we discussed earlier [8]. Fatty acids in SGS have been proposed to act as insecticides against ants or other harmful arthropods as they are thought to be

Chemo-enzymatic total synthesis: current approaches toward the integration of chemical and enzymatic transformations

• Ryo Tanifuji and
• Hiroki Oguri

Beilstein J. Org. Chem. 2024, 20, 1693–1712, doi:10.3762/bjoc.20.151

• oxidation of phenols on A- and E-rings, yield bisquinone 94. The membrane-bound peptidase SfmE excises the long-chain fatty acid moiety on the N-terminus of the C1 side chain. Secretion through the efflux pump SfmG, and extracellular oxidative deamination catalyzed by the berberine bridge enzyme (BBE)-like

• the attachment and detachment of the fatty acid moiety. The myristic acid, introduced by SfmA at the beginning, is not attached in the final product 5. However, detailed investigations by Oikawa and co-workers clearly demonstrated that this fatty acid is essential for SfmC-catalyzed scaffold assembly

• fatty acid moiety on the C1 side chain (Scheme 9). Although the enzymatic deacylation of 94 can be catalyzed by the membrane-bound peptidase SfmE, similar chemical transformations require harsh conditions and are difficult to perform in the presence of highly reactive functional groups. To circumvent

Polymer degrading marine Microbulbifer bacteria: an un(der)utilized source of chemical and biocatalytic novelty

• Weimao Zhong and
• Vinayak Agarwal

Beilstein J. Org. Chem. 2024, 20, 1635–1651, doi:10.3762/bjoc.20.146

• classes of natural products isolated from Microbulbifer to date include alkaloids [15], fatty acid and polyketides [16][17], and non-ribosomally synthesized peptides [3][4][7]. These findings validate the potential for secondary metabolite discovery from Microbulbifer genus. This review will cover the

• interactions in the marine environment may be broadly shared [132]. Further examples of shared natural products are delineated below. Aliphatic and aromatic hydrocarbons (2Z,4E)-3-Methyl-2,4-decadienoic acid (25, Figure 9), an unsaturated fatty acid with unusual methylation pattern was isolated and identified

• group in 25 is rare. Feeding [1-13C]acetate to the culture resulted the enrichment of C1, C3, C5, C7, and C9 carbons, which verified the origin of the carbon skeleton as being fatty acid-derived. Feeding experiments with ʟ-[methyl-13C]methionine yielded only enrichment of C11 methyl, indicating that

Sustainable tandem acylation/Diels–Alder reaction toward versatile tricyclic epoxyisoindole-7-carboxylic acids in renewable green solvents

• Ayhan Yıldırım

Beilstein J. Org. Chem. 2024, 20, 1308–1319, doi:10.3762/bjoc.20.114

• developed in this study, isolated double bonds in the fatty acid chains in sunflower oil do not undergo a side ene reaction with maleic anhydride, which requires high temperatures and/or metal catalysts, since the IMDAF reaction can be performed at 50 ºC or room temperature (Scheme 2) [125][126]. The olefin

Manganese-catalyzed C–C and C–N bond formation with alcohols via borrowing hydrogen or hydrogen auto-transfer

• Mohd Farhan Ansari,
• Atul Kumar Maurya,
• Abhishek Kumar and
• Saravanakumar Elangovan

Beilstein J. Org. Chem. 2024, 20, 1111–1166, doi:10.3762/bjoc.20.98

• ketone led to the linear α-alkylated product, followed by the alkylation of the methylene ketone with the second benzyl alcohol then afforded the dialkylated product. Remarkably, the drug donepezil, a steroid derivative and a fatty acid derivative were synthesized using this procedure (Scheme 29B). In

(Bio)isosteres of ortho- and meta-substituted benzenes

• H. Erik Diepers and
• Johannes C. L. Walker

Beilstein J. Org. Chem. 2024, 20, 859–890, doi:10.3762/bjoc.20.78

• ]. The ability of 1,5-BCHeps to act as bioisosteres of meta-benzenes was also studied by Anderson and co-workers. They reported the comparison of fatty acid amide hydrolase inhibitor URB597 with its 1,5-BCHep isostere 146 (Figure 21) [27]. They found that while replacement of one of the meta-benzenes

Substrate specificity of a ketosynthase domain involved in bacillaene biosynthesis

• Zhiyong Yin and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2024, 20, 734–740, doi:10.3762/bjoc.20.67

• only for the incorporation of one extender unit [2][3]. Although enzyme domains with various specialised catalytic functions can be found as integral part of polyketide synthases, three domain types are fundamental to their biosynthesis, resembling the same logic as observed for fatty acid biosynthesis

New variochelins from soil-isolated Variovorax sp. H002

• Jabal Rahmat Haedar,
• Aya Yoshimura and
• Toshiyuki Wakimoto

Beilstein J. Org. Chem. 2024, 20, 692–700, doi:10.3762/bjoc.20.63

• serine (Ser), a β-hydroxyaspartic acid (Hya), and a unique γ-amino acid biosynthetically originating from an arginine and a methyl malonate (4-amino-7-guanidino-3-hydroxy-2-methylheptanoic acid), with the amino group acylated by a saturated fatty acid. Subsequent HMBC and MS/MS analyses indicated that

• moiety (Figure 1 and Figure S18 in Supporting Information File 1). Subsequently, to determine the acyl chain, the hydrolysate of 3 was treated with 2-amino-2-methyl-1-propanol to yield a 4,4-dimethyloxazoline (DMOX) derivative of the fatty acid, which was then subjected to GC–MS [14][15]. The EIMS of the

• Information File 1). Preparation of fatty acid methyl ester (FAME) derivatives 0.1 mg of 1 or 2 were hydrolyzed with 6 M HCl at 110 °C overnight. The obtained hydrolysates were freeze dried, resuspended in 100 µL of methanol, and then treated with 100 µL of trimethylsilyldiazomethane, and the mixtures were

Chemical and biosynthetic potential of Penicillium shentong XL-F41

• Ran Zou,
• Xin Li,
• Xiaochen Chen,
• Yue-Wei Guo and
• Baofu Xu

Beilstein J. Org. Chem. 2024, 20, 597–606, doi:10.3762/bjoc.20.52

• investigations, accompanied by fermentation media optimization, of a newly isolated fungus, Penicillium shentong XL-F41, led to the isolation of twelve compounds. Among these are two novel indole terpene alkaloids, shentonins A and B (1 and 2), and a new fatty acid 3. Shentonin A (1) is distinguished by an

• stimulating the production of a greater number of metabolite peaks, as shown in Figure 1. Scaled-up fermentation allowed us to isolate and characterize two new indole terpene alkaloids, shentonins A and B (1 and 2), a new fatty acid 3, and nine previously identified compounds 4–12, among which were gram

• sixteen-carbon fatty acid. Notably, two methylene carbons overlapped in the 13C NMR spectrum. The COSY correlations facilitated the determination of the carbon chain fragments from C-11 to C-16 and C-2 to C-10, despite two methylene signals overlapping. The carboxyl group's position at C-1 was confirmed

Synthesis and biological profile of 2,3-dihydro[1,3]thiazolo[4,5-b]pyridines, a novel class of acyl-ACP thioesterase inhibitors

• Jens Frackenpohl,
• David M. Barber,
• Guido Bojack,
• Birgit Bollenbach-Wahl,
• Ralf Braun,
• Rahel Getachew,
• Sabine Hohmann,
• Kwang-Yoon Ko,
• Karoline Kurowski,
• Bernd Laber,
• Rebecca L. Mattison,
• Thomas Müller,
• Anna M. Reingruber,
• Dirk Schmutzler and
• Andrea Svejda

Beilstein J. Org. Chem. 2024, 20, 540–551, doi:10.3762/bjoc.20.46

• with emphasis on the structural diversity of small-molecule ligands. In this context, acyl-acyl carrier protein (acyl-ACP) thioesterase inhibitors have shown a remarkable variability. Fatty acid thioesterase (FAT) enzymes represent a family of proteins exclusively found in higher plants. They mediate

Identification of the p-coumaric acid biosynthetic gene cluster in Kutzneria albida: insights into the diazotization-dependent deamination pathway

• Seiji Kawai,
• Akito Yamada,
• Yohei Katsuyama and
• Yasuo Ohnishi

Beilstein J. Org. Chem. 2024, 20, 1–11, doi:10.3762/bjoc.20.1

• CmaA1. 3-ACA (3) is then synthesized from 3,4-AHBA-CmaA3 and malonyl-CmaA2 by the highly reducing type II PKS composed of four Cma proteins (CmaA4, CmaA5, CmaB, and CmaG), a dehydratase from fatty acid synthase, and an unknown thioesterase. CmaB should also stimulate the reaction in an unknown manner as

• the activity of CmaG (a putative FMN-dependent oxidoreductase), it is expected to catalyze the reduction of the keto group of an β-ketoacyl intermediate, similar to the ketoreductase of fatty acid synthase (FAS) and highly reducing type II PKS. This hypothesis is supported by the fact that cmaG exists

Synthesis of ether lipids: natural compounds and analogues

• Marco Antônio G. B. Gomes,
• Alicia Bauduin,
• Chloé Le Roux,
• Romain Fouinneteau,
• Wilfried Berthe,
• Mathieu Berchel,
• Hélène Couthon and
• Paul-Alain Jaffrès

Beilstein J. Org. Chem. 2023, 19, 1299–1369, doi:10.3762/bjoc.19.96

Intermediates and shunt products of massiliachelin biosynthesis in Massilia sp. NR 4-1

• Till Steinmetz,
• Blaise Kimbadi Lombe and
• Markus Nett

Beilstein J. Org. Chem. 2023, 19, 909–917, doi:10.3762/bjoc.19.69

• Burkholderia gladioli, which possesses an unprecedented citrate-derived fatty acid moiety [11]. Furthermore, lipopeptide siderophores with photocleavable moieties, like taiwachelin, were reported from bacteria of the genera Cupriavidus and Variovorax [12][13][14]. The β-proteobacterial genus Massilia was

Discrimination of β-cyclodextrin/hazelnut (Corylus avellana L.) oil/flavonoid glycoside and flavonolignan ternary complexes by Fourier-transform infrared spectroscopy coupled with principal component analysis

• Nicoleta G. Hădărugă,
• Gabriela Popescu,
• Dina Gligor (Pane),
• Cristina L. Mitroi,
• Sorin M. Stanciu and
• Daniel Ioan Hădărugă

Beilstein J. Org. Chem. 2023, 19, 380–398, doi:10.3762/bjoc.19.30

• principal component analysis (FTIR–PCA). These innovative complexes combine the characteristics of the three components and improve the properties of the resulting material such as the onsite protection against oxidative degradation of hazelnut oil unsaturated fatty acid glycerides. Also, the apparent water

• solubility and bioaccessibility of the hazelnut oil components and antioxidants can be increased, as well as the controlled release of bioactive compounds (fatty acid glycerides and antioxidant flavonoids, namely hesperidin, naringin, rutin, and silymarin). The appropriate method for obtaining the ternary

• and animal fat components that especially consist of fatty acid (FA) triglycerides are appropriate guest molecules for obtaining CD-based complexes. The hydrophobic long-chain moieties of the FA glycerides allow obtaining CD:FA glyceride complexes at various molar ratios [8][9], with increased

Identification and determination of the absolute configuration of amorph-4-en-10β-ol, a cadinol-type sesquiterpene from the scent glands of the African reed frog Hyperolius cinnamomeoventris

• Angelique Ladwig,
• Markus Kroll and
• Stefan Schulz

Beilstein J. Org. Chem. 2023, 19, 167–175, doi:10.3762/bjoc.19.16

• scent gland macrolides can be biosynthesized by the frogs [7], although the macrolides are produced from the fatty acid biosynthetic pathway. The gas chromatographic separation obtained with the chiral phase also allowed the determination of the identity of the minor diastereomers formed during the

Insight into oral amphiphilic cyclodextrin nanoparticles for colorectal cancer: comprehensive mathematical model of drug release kinetic studies and antitumoral efficacy in 3D spheroid colon tumors

• Sedat Ünal,
• Gamze Varan,
• Juan M. Benito,
• Yeşim Aktaş and
• Erem Bilensoy

Beilstein J. Org. Chem. 2023, 19, 139–157, doi:10.3762/bjoc.19.14

• also have increased. The 6-O-capro-β-CD and poly-β-CD-C6 derivatives used in the study are cyclodextrin derivatives with the same core structure. Heptakis(6-O-hexanoyl)-β-CD (6-O-capro-β-CD) is a primary face-modified amphiphilic CD derivative with a 6C fatty acid chain attached via an ester bond to

Nostochopcerol, a new antibacterial monoacylglycerol from the edible cyanobacterium Nostochopsis lobatus

• Naoya Oku,
• Saki Hayashi,
• Yuji Yamaguchi,
• Hiroyuki Takenaka and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2023, 19, 133–138, doi:10.3762/bjoc.19.13

• limited number of attempts include an antifungal lipopeptide nostofungicidine [4] and an antioxidant nostocionone [5] from Nostoc commune, an unusual antibacterial n−1 fatty acid from N. verrucosum [2], and the sacrolides, antimicrobial oxylipin macrolactones from Aphanothece sacrum [6][7]. Nostochopsis

• , 129.1, and 128.9) observed in the 13C NMR spectrum (Table 1), revealing that compound 1 has a linear structure. The 1H NMR spectrum contained resonances typical of an unsaturated fatty acid, such as non-conjugated olefins with four-proton integration (δH ca. 5.34–5.32, 4H), a bisallylic methylene (δH

• signals (δH 1.62 and ca. 1.39–1.30) were observed, implying that compound 1 is a derivative of a fatty acid. Indeed, all oxygenated protons constituted a spin system (CH21'–CH2'–CH23') in the COSY spectrum (Figure 1), and considering the lack of any terminal group besides CH316, monoacylglycerol was the

Digyalipopeptide A, an antiparasitic cyclic peptide from the Ghanaian Bacillus sp. strain DE2B

• Adwoa P. Nartey,
• Aboagye K. Dofuor,
• Kofi B. A. Owusu,
• Anil S. Camas,
• Hai Deng,
• Marcel Jaspars and
• Kwaku Kyeremeh

Beilstein J. Org. Chem. 2022, 18, 1763–1771, doi:10.3762/bjoc.18.185

• acid sequence in the cyclic peptide backbone but differing only by the length of aliphatic fatty acid side chains. When tested against Trypanosoma brucei subsp. brucei strain GUTat 3.1 and Leishmania donovani (Laveran and Mesnil) Ross (D10), digyalipopeptide A (1) gave IC50 values of 12.89 µM (suramin

• File 1). However, it was difficult to determine the absolute stereochemistry around the esterified methine carbon C-39 (δC 71.6) of the fatty acid chain. In the absence of an authentic laboratory standard for the fatty acid chain coupled with the inability to obtain well-defined multiplicity patterns

• to confirm the presence of the cyclic ester and the possible absolute stereochemistry around C-39 (δC 71.6) of the fatty acid chain we first of all consulted the global natural products social molecular networking (GNPS) [19][20][21]. The GNPS network data (Figure 6) provided the opportunity to

Navigating and expanding the roadmap of natural product genome mining tools

• Friederike Biermann,
• Sebastian L. Wenski and
• Eric J. N. Helfrich

Beilstein J. Org. Chem. 2022, 18, 1656–1671, doi:10.3762/bjoc.18.178

• secondary metabolite biosynthetic enzymes are distant paralogs of enzymes involved in primary metabolism [63][71]. These NP biosynthetic enzymes are hypothesized to have undergone significant sequence and selectivity changes while still operating based on the same reaction mechanism (e.g., fatty acid

A new route for the synthesis of 1-deazaguanine and 1-deazahypoxanthine

• Raphael Bereiter,
• Marco Oberlechner and
• Ronald Micura

Beilstein J. Org. Chem. 2022, 18, 1617–1624, doi:10.3762/bjoc.18.172

• , glycogen synthase kinase 3 (GSK-3), leucine-rich repeat kinase 2 (LRRK2), tyrosine phosphorylation-regulated kinase-1A (DYRK1A) and CDC2-like kinase 1 (CLK1), and fatty acid amide hydrolase (FAAH) [4]). Similar properties were ascertained for 1-deazapurine derivatives (imidazo[4,5-b]pyridines) and

New azodyrecins identified by a genome mining-directed reactivity-based screening

• Atina Rizkiya Choirunnisa,
• Kuga Arima,
• Yo Abe,
• Noritaka Kagaya,
• Kei Kudo,
• Hikaru Suenaga,
• Junko Hashimoto,
• Manabu Fujie,
• Noriyuki Satoh,
• Kazuo Shin-ya,
• Kenichi Matsuda and
• Toshiyuki Wakimoto

Beilstein J. Org. Chem. 2022, 18, 1017–1025, doi:10.3762/bjoc.18.102

• installation of a cis-olefin on the 1,2-positions of the alkyl side chain would afford azodyrecins A–C (1–3), in a reaction likely to be mediated by Ady9, a putative fatty acid desaturase. Nevertheless, the possibility that the desaturation occurs prior to the methyl esterification could not be excluded. The

Amamistatins isolated from Nocardia altamirensis

• Till Steinmetz,
• Wolf Hiller and
• Markus Nett

Beilstein J. Org. Chem. 2022, 18, 360–367, doi:10.3762/bjoc.18.40

• -type siderophores. Structurally, compounds 1–5 are closely related to formobactin [10], brasilibactin [23], nocardimicin [24], and terpenibactins [15]. While the core scaffold of these natural products is conserved, they differ in the length of their fatty acid residues, their methylation pattern, and

Unsaturated fatty acids and a prenylated tryptophan derivative from a rare actinomycete of the genus Couchioplanes

• Shun Saito,
• Kanji Indo,
• Naoya Oku,
• Hisayuki Komaki,
• Masashi Kawasaki and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2021, 17, 2939–2949, doi:10.3762/bjoc.17.203

• were weakly inhibitory against Kocuria rhizophila at MIC 100 μg/mL and none were cytotoxic against P388 at the same concentration. Keywords: Couchioplanes; prenylated tryptophan; rare actinomycete; unsaturated fatty acid; Introduction Actinomycetes, a subgroup of filamentous Gram-positive bacteria

• , a similarly methyl-branched unsaturated fatty acid ester, which is produced by type I polyketide synthase in a Streptomyces strain by a heterologous expression experiment [33]. These facts suggest that 1–5 could be byproducts from the biosynthesis of larger polyketides, but further investigation is

Chemical approaches to discover the full potential of peptide nucleic acids in biomedical applications

• Nikita Brodyagin,
• Martins Katkevics,
• Venubabu Kotikam,
• Christopher A. Ryan and
• Eriks Rozners

Beilstein J. Org. Chem. 2021, 17, 1641–1688, doi:10.3762/bjoc.17.116

A comprehensive review of flow chemistry techniques tailored to the flavours and fragrances industries

• Guido Gambacorta,
• James S. Sharley and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2021, 17, 1181–1312, doi:10.3762/bjoc.17.90