Synthesis of the aggregation pheromone of Tribolium castaneum

• Biyu An,
• Xueyang Wang,
• Ao Jiao,
• Qinghua Bian and
• Jiangchun Zhong

Beilstein J. Org. Chem. 2025, 21, 510–514, doi:10.3762/bjoc.21.38

• coupling, and finally leads to the target pheromones by olefin oxidation with RuCl3/NaIO4. Results and Discussion The retrosynthetic analysis of the aggregation pheromone (4R,8R)-1 is shown in Scheme 1. Obviously, the target pheromone (4R,8R)-1 could be synthesized via an oxidation of chiral terminal

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

• , proline-containing diketopiperazines were identified for the first time in snake scent glands, although an artificial formation from amino acids likely present in the secretion cannot be excluded. Keywords: carboxylic acids; identification; mass spectrometry; pheromones; snakes; Introduction Located in

• animal kingdom that serve as signals, such as the aldehydes syn-4,6-dimethylundecanal and 4,6-dimethyldodecanal and their corresponding alcohols, which act as male sex and trail-following pheromones in termites [31][32]. Diketopiperazines The GC–MS analysis also revealed the presence of at least five

Total synthesis: an enabling science

• Bastien Nay

Beilstein J. Org. Chem. 2023, 19, 474–476, doi:10.3762/bjoc.19.36

• [12], as illustrated in this thematic issue with the synthesis of pheromones [16]. This requires permanent technological progress. Thus, the recent boom of artificial intelligence, machine learning, and computational chemistry for retrosynthetic analyses and beyond foreshadows a renewed interest in

Total synthesis of insect sex pheromones: recent improvements based on iron-mediated cross-coupling chemistry

• Eric Gayon,
• Guillaume Lefèvre,
• Olivier Guerret,
• Adrien Tintar and
• Pablo Chourreu

Beilstein J. Org. Chem. 2023, 19, 158–166, doi:10.3762/bjoc.19.15

• insect sex pheromones as an alternative to conventional pesticides is in constant growth. In this report, we discuss the recent contributions brought by our groups in the field of iron-catalyzed cross-couplings applied to the synthesis of insect pheromones. The pivotal question of the development of

• sustainable synthetic procedures involving cheap, non-toxic and efficient additives is also discussed, as well as the mechanistic features guiding the reactivity of such catalytic systems. Keywords: catalysis; cross-coupling; insect pheromones; iron; Introduction Public health issues related to

• mechanisms to help regulate/balance the populations of harmful species rather than eradicating them) based on the use of insect pheromones [2][3][4][5] is an eco-friendly solution for the protection of a wide range of crops and plants against pests. Indeed, those chemical mediators, which are emitted by

Prins cyclization-mediated stereoselective synthesis of tetrahydropyrans and dihydropyrans: an inspection of twenty years

• Asha Budakoti,
• Pradip Kumar Mondal,
• Prachi Verma and
• Jagadish Khamrai

Beilstein J. Org. Chem. 2021, 17, 932–963, doi:10.3762/bjoc.17.77

• ; Prins cyclization; stereoselective; tetrahydropyran; Introduction 6-Membered saturated oxygen heterocycles, known as tetrahydropyran (THP), are recognized as privileged scaffolds, present in a variety of biologically important natural products, such as polyether antibiotics, marine toxins, pheromones

3-Acetoxy-fatty acid isoprenyl esters from androconia of the ithomiine butterfly Ithomia salapia

• Florian Mann,
• Daiane Szczerbowski,
• Lisa de Silva,
• Melanie McClure,
• Marianne Elias and
• Stefan Schulz

Beilstein J. Org. Chem. 2020, 16, 2776–2787, doi:10.3762/bjoc.16.228

• spectrometry; mimicry; pheromones; pyrrolizidine alkaloids; Introduction The Neotropical butterfly tribe Ithomiini (Nymphalidae: Danainae) is very diverse and species-rich, with over 390 species and 50 genera [1][2] and extensively involved in Müllerian mimetic interactions [3]. Ithomiines are well suited for

• multiple factors, notably non-random mating based on color pattern and/or sexual pheromones [6][7][8]. Determining whether the closely related subspecies of I. salapia differ in the chemical composition of volatiles is, therefore, of great interest. All male ithomiine butterflies, including Ithomia

• , possess scent glands on their forewings, so-called androconia, covered with erectable hairpencils (Figure 1). They are used during courtship and are known to contain compounds acting as pheromones for the butterflies [2]. Adult ithomiines sequester pyrrolizidine alkaloids (PAs) pharmacophagously from

Synthesis of disparlure and monachalure enantiomers from 2,3-butanediacetals

• Adam Drop,
• Hubert Wojtasek and
• Bożena Frąckowiak-Wojtasek

Beilstein J. Org. Chem. 2020, 16, 616–620, doi:10.3762/bjoc.16.57

• unsymmetrically substituted cis-epoxides. The procedure was applied for the preparation of both enantiomers of disparlure and monachalure, the components of the sex pheromones of the gypsy moth (Lymantria dispar) and the nun moth (Lymantria monacha) using methyl (2S,3R,5R,6R)-3-ethylsulfanylcarbonyl-5,6-dimethoxy

• semiochemicals. They have been frequently found as pheromones in lepidopteran species of the families Noctuidae, Arctiidae, Lymantridae, Geometridae and Erebidae [1]. (3Z,9Z)-6S,7R-Epoxyheneicosa-3,9-diene, a constituent of the female sex pheromone of the moth Tetanolita mynesalis (Erebidae) [2] is a

• ranging from 0 to 64% and the results were not reproducible. We could not identify the reason of these problems and could not overcome them. So, although compound 15 seemed an attractive starting material for introducing alkyl chains of pheromones 1–4, we decided to abandon this substrate and use aldehyde

Copper-catalyzed enantioselective conjugate addition of organometallic reagents to challenging Michael acceptors

• Delphine Pichon,
• Jennifer Morvan,
• Christophe Crévisy and
• Marc Mauduit

Beilstein J. Org. Chem. 2020, 16, 212–232, doi:10.3762/bjoc.16.24

• enantioselectivities (dr up to 99:1 and ee up to >99.5). The value of the protocol was successfully illustrated through the enantioselective total syntheses of (−)-lasiol and (+)-faranal, two useful natural pheromones. Shortly after, Feringa, Minnaard, and co-workers demonstrated the efficiency of (S,R)-reversed

Terpenes

• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2019, 15, 2966–2967, doi:10.3762/bjoc.15.292

• pheromones, but also have a long standing history as fragrances used by humans. The oxidised derivatives may be of high interest because of their bioactivity, with some of the most important drugs used in medical applications being of terpenoid origin. Two of the most fanous examples include the diterpenoid

Bacterial terpene biosynthesis: challenges and opportunities for pathway engineering

• Eric J. N. Helfrich,
• Geng-Min Lin,
• Christopher A. Voigt and
• Jon Clardy

Beilstein J. Org. Chem. 2019, 15, 2889–2906, doi:10.3762/bjoc.15.283

• functional roles, which range from widely distributed metabolites like cholesterol, to those with more restricted distribution like vitamins A and D, carotenoids, and steroid hormones, to some with highly restricted distribution like pheromones, fragrances, and defense metabolites [2][3]. Many of the more

Harnessing enzyme plasticity for the synthesis of oxygenated sesquiterpenoids

• Melodi Demiray,
• David J. Miller and
• Rudolf K. Allemann

Beilstein J. Org. Chem. 2019, 15, 2184–2190, doi:10.3762/bjoc.15.215

• healthcare and agriculture as well as the potential to tailor their properties to specific needs. For example, fluorinated derivatives of (E)-β-farnesene, a potent alarm pheromone for aphids [20][21][22][23], are more effective as pheromones than the parent compound, and finding high potency derivatives of

Diastereo- and enantioselective preparation of cyclopropanol derivatives

• Marwan Simaan and
• Ilan Marek

Beilstein J. Org. Chem. 2019, 15, 752–760, doi:10.3762/bjoc.15.71

• transformations [1]. The cyclopropane subunit is also present in many biologically important compounds such as pheromones, fatty acid metabolites, unusual amino acids and possess interesting herbicidal, insecticidal, antibiotic, antibacterial, antifungal, antiviral and antitumor activities [2]. For these reasons

Aqueous olefin metathesis: recent developments and applications

• Valerio Sabatino and
• Thomas R. Ward

Beilstein J. Org. Chem. 2019, 15, 445–468, doi:10.3762/bjoc.15.39

• applications of olefin metathesis in chemical biology were reported with “ill-defined” catalysts such as RuCl3·H2O to synthesize insect pheromones by olefin metathesis [77][78]. The development of well-defined ruthenium-based catalysts increased the number of olefin metathesis applications in chemical biology

Pd(OAc)₂/Ph₃P-catalyzed dimerization of isoprene and synthesis of monoterpenic heterocycles

• Dominik Kellner,
• Maximilian Weger,
• Andrea Gini and
• Olga García Mancheño

Beilstein J. Org. Chem. 2017, 13, 1807–1815, doi:10.3762/bjoc.13.175

• various other derivatives such as pheromones and fragrances. Though isoprene was initially obtained from thermal decomposition of natural rubber [18][19], nowadays it is mostly produced industrially as a byproduct of the cracking of naphtha or oil [20]. Recently, the bacterial production of bio-isoprene

Posttranslational isoprenylation of tryptophan in bacteria

• Masahiro Okada,
• Tomotoshi Sugita and
• Ikuro Abe

Beilstein J. Org. Chem. 2017, 13, 338–346, doi:10.3762/bjoc.13.37

• same scaffold as that of the ComX pheromones, but with the opposite stereochemistry. This review highlights the biosynthetic pathways and posttranslational isoprenylation of tryptophan. In particular, recent studies on peptide modifying enzymes are discussed. Keywords: Bacillus subtilis

• referred to as the farnesylation or geranylgeranylation of the thiol group of the C-terminal cysteine residue in peptides and proteins [4][5][6][7]. The isoprenylation of cysteine was first found in the peptide pheromones of basidiomycetous yeast [8][9][10]. Two peptide pheromones, tremerogen A-10 and

• because of a high proliferation rate. In the quorum sensing process, bacteria constitutively secrete specific extracellular signaling molecules, called quorum sensing pheromones, to gather information about their cell population density [15][16][17][18]. Various phenomena are stimulated by an increase in

Diels–Alder reactions of myrcene using intensified continuous-flow reactors

• Christian H. Hornung,
• Miguel Á. Álvarez-Diéguez,
• Thomas M. Kohl and
• John Tsanaktsidis

Beilstein J. Org. Chem. 2017, 13, 120–126, doi:10.3762/bjoc.13.15

• model compound for a series of different reactions and in the synthesis of complex natural products, including several pheromones [3]. Myrcene is a colorless oil and exists as two isomers, the synthetic α-myrcene, containing an isopropenyl group, and the naturally occurring β-myrcene (which will be

Identification, synthesis and mass spectrometry of a macrolide from the African reed frog Hyperolius cinnamomeoventris

• Markus Menke,
• Pardha Saradhi Peram,
• Iris Starnberger,
• Walter Hödl,
• Gregory F.M. Jongsma,
• David C. Blackburn,
• Mark-Oliver Rödel,
• Miguel Vences and
• Stefan Schulz

Beilstein J. Org. Chem. 2016, 12, 2731–2738, doi:10.3762/bjoc.12.269

• basis of its EI mass spectrum. The occurrence of characteristic ions can be explained by the fragmentation pathway proposed in the article. In contrast, the localization of a double bond in many aliphatic open-chain compounds like alkenes, alcohols or acetates, important structural classes of pheromones

• ; pheromones; Introduction The lactone motif is found in many compounds that are used in chemical communication. Among them, macrocyclic lactones are an important class because of their biosynthetic availability and their inherent compound properties. During the biosynthesis of macrocyclic lactones, a fatty

• therefore repeatedly invented during evolution and are used by different animals such as bees, beetles, butterflies, cockroaches, or frogs as pheromones [1]. Finding and choosing mates in frogs is usually regarded as being primarily acoustically mediated. Nevertheless, some families like the Mantellidae

Biosynthesis of α-pyrones

• Till F. Schäberle

Beilstein J. Org. Chem. 2016, 12, 571–588, doi:10.3762/bjoc.12.56

• ), represent widely exploited building blocks in synthetic chemistry. Examples are the syntheses of compounds like α-chymotrypsin, coumarins, pheromones, and solanopyrones [1]. Known biological functions reach from intermediates and end products in primary metabolism to signaling molecules and molecules which

• -pyrone derivatives for their antimicrobial and cytotoxic properties [2]. The volatile α-pyrone 5-(2,4-dimethylheptyl)-3-methyl-2H-pyran-2-one (7, Figure 1), also named supellapyrone) is used by female brownbanded cockroaches to attract males [13]. It is known that cockroaches use pheromones in many

Highly selective palladium–benzothiazole carbene-catalyzed allylation of active methylene compounds under neutral conditions

• Antonio Monopoli,
• Pietro Cotugno,
• Carlo G. Zambonin,
• Francesco Ciminale and
• Angelo Nacci

Beilstein J. Org. Chem. 2015, 11, 994–999, doi:10.3762/bjoc.11.111

• allylation; Introduction The α-allylation of carbonyl compounds is one of the most important reactions in organic chemistry, since it opens the way to the synthesis of a plethora of interesting molecules such as pheromones, perfumes, or bio-active compounds such as prostaglandin E2 or F2α. After the

Structure elucidation of female-specific volatiles released by the parasitoid wasp Trichogramma turkestanica (Hymenoptera: Trichogrammatidae)

• Armin Tröger,
• Teris A. van Beek,
• Martinus E. Huigens,
• Isabel M. M. S. Silva,
• Maarten A. Posthumus and
• Wittko Francke

Beilstein J. Org. Chem. 2014, 10, 767–773, doi:10.3762/bjoc.10.72

• those of the oligomethylpolyenes known as pheromones of nitidulid beetles [24]. The 4-methyl-2E,4E-diene motif has been known as a substructure of pheromones of beetles, cockroaches and scale insects [16]. Whether these compounds are insect-produced or products of (endo)symbionts will need further

Asymmetric total synthesis of a putative sex pheromone component from the parasitoid wasp Trichogramma turkestanica

• Danny Geerdink,
• Jeffrey Buter,
• Teris A. van Beek and
• Adriaan J. Minnaard

Beilstein J. Org. Chem. 2014, 10, 761–766, doi:10.3762/bjoc.10.71

• of 4.4%. Keywords: asymmetric catalysis; copper; deoxypropionates; natural products; sex pheromone; Trichogramma turkestanica; Introduction Communication by means of pheromones is common in many animal species. For instance, many insects secrete air-borne volatiles to attract a mate for generating

• similar making a taxonomic characterization at the species level difficult [4]. A classification on the basis of sex pheromones might help in this respect. Apart from the above reason and the scientific challenge to elucidate the identity of a complex pheromone at the low nanogram level, an additional

• from 6. Both the enantiomeric excess and the diastereomeric excess of 8 were excellent which is important as the response of insects to their pheromones can be highly sensitive to the stereoisomeric composition. A number of procedures exist to reduce ketones to their corresponding methylene groups

A protecting group-free synthesis of the Colorado potato beetle pheromone

• Zhongtao Wu,
• Manuel Jäger,
• Jeffrey Buter and
• Adriaan J. Minnaard

Beilstein J. Org. Chem. 2013, 9, 2374–2377, doi:10.3762/bjoc.9.273

• [9], Chauhan [10] and very recently by Faraldos [11] respectively, and the first field evaluation of synthetic (S)-1 in a trap crop pest management strategy showed its practical utility [1]. The commercial enantioselective production of chiral pheromones of many pest insects is hampered by

Some aspects of radical chemistry in the assembly of complex molecular architectures

• Béatrice Quiclet-Sire and
• Samir Z. Zard

Beilstein J. Org. Chem. 2013, 9, 557–576, doi:10.3762/bjoc.9.61

• -diol on one of the alkenes would in principle result in the formation of a cyclic ketal. Spiro and cyclic ketals are ubiquitous in pheromones and in marine natural products [51]. The comparatively long effective lifetime of radicals generated under the conditions of the xanthate transfer may be

On the proposed structures and stereocontrolled synthesis of the cephalosporolides

• Sami F. Tlais and
• Gregory B. Dudley

Beilstein J. Org. Chem. 2012, 8, 1287–1292, doi:10.3762/bjoc.8.146

• norhalichondrin [13][14]. Spiroketal-containing pheromones are especially prominent in insect communication, with the spiroketal stereochemistry often relaying important information [15]. For example, the R-enantiomer of the olive-fly sex pheromone is attractive to males, while the S-enantiomer attracts females

Stereoselective synthesis of trans-fused iridoid lactones and their identification in the parasitoid wasp Alloxysta victrix, Part I: Dihydronepetalactones

• Nicole Zimmermann,
• Robert Hilgraf,
• Lutz Lehmann,
• Daniel Ibarra and
• Wittko Francke

Beilstein J. Org. Chem. 2012, 8, 1246–1255, doi:10.3762/bjoc.8.140

• species [12], while nepetalactone and the corresponding lactol showing (1R)-configuration have been identified as pheromones of aphids [13][14]. (1R,4S,4aR,7S,7aR)-Dihydronepetalactol (8) was characterized as a semiochemical for lacewings [15]. The dihydronepetalactone skeleton shows four contiguous