Beyond symmetric self-assembly and effective molarity: unlocking functional enzyme mimics with robust organic cages

• Keith G. Andrews

Beilstein J. Org. Chem. 2025, 21, 421–443, doi:10.3762/bjoc.21.30

• ) [38]. To capture both stability and solubility, we turned to Mastalerz’s post-functionalization chemistry [286][300][304][306][358][359][360][361][362], in which imines are oxidized by a Pinnick oxidation to amides [286][360][363][364], an approach gaining popularity [46][262]. Importantly, we were

• able to adapt this chemistry to work in situ, allowing soluble metastable imine frameworks to be trapped as amides [38]. The adapted cages were soluble, and were now stable enough to be purified by gel-permeation (size-exclusion) chromatography (useful when precipitation is not possible), which is

Dioxazolones as electrophilic amide sources in copper-catalyzed and -mediated transformations

• Seungmin Lee,
• Minsuk Kim,
• Hyewon Han and
• Jongwoo Son

Beilstein J. Org. Chem. 2025, 21, 200–216, doi:10.3762/bjoc.21.12

• leads to the formation of the N-acyl amidine product 10. 1.4 N-Arylation of dioxazolones Amides bearing N-substituents are key structural motifs in a wide range of polymers [82], natural products [83], and pharmaceuticals [84][85]. Conventional synthetic routes for N-arylamides typically involve the

• Synthesis of primary amides via the generation of copper–imidate radical intermediates In a subsequent study, the research group of Son developed a method for the reduction of dioxazolones to synthesize primary amides under mild reducing conditions in copper catalysis (Scheme 10) [103]. The reaction was

• conducted using a catalytic amount of copper acetate and a phenanthroline ligand, with a stoichiometric amount of silane serving as the reductant. Both aryl- and alkyl-substituted dioxazolones proved to be compatible under the standard reaction conditions, yielding the desired primary amides 28a–f. Notably

Recent advances in electrochemical copper catalysis for modern organic synthesis

• Yemin Kim and
• Won Jun Jang

Beilstein J. Org. Chem. 2025, 21, 155–178, doi:10.3762/bjoc.21.9

• of substrates, including arylacetylenes with electron-donating and electron-withdrawing groups, and ferrocenyl amides with alkyl and acyl substituents on the other Cp ring. Additionally, the reaction showed similar reactivity and enantioselectivity on a 1 mmol scale. In 2020, Mei et al. reported the

Reactivity of hypervalent iodine(III) reagents bearing a benzylamine with sulfenate salts

• Beatriz Dedeiras,
• Catarina S. Caldeira,
• José C. Cunha,
• Clara S. B. Gomes and
• M. Manuel B. Marques

Beilstein J. Org. Chem. 2024, 20, 3281–3289, doi:10.3762/bjoc.20.272

• have been reported [12]. These reagents have proven effective in delivering azides (I) [13], amides (II) [14], aliphatic cyclic amines (III) [15], phthalimidates (IV) [16], imines (V) [17], sulfoximides (VI) [18], carbazoles (VII) [19], secondary (VIII) [4] and primary (IX) [20] amines (Figure 1). The

Intramolecular C–H arylation of pyridine derivatives with a palladium catalyst for the synthesis of multiply fused heteroaromatic compounds

• Yuki Nakanishi,
• Shoichi Sugita,
• Kentaro Okano and
• Atsunori Mori

Beilstein J. Org. Chem. 2024, 20, 3256–3262, doi:10.3762/bjoc.20.269

• % yield. The yield is improved to 94% when the reaction is performed with PPh3 as a ligand of palladium. The reaction is examined with amides derived from unsubstituted picoline, 6-methylpicoline, and 2,6-pyridinedicarboxylic acid in a similar manner to afford the cyclized products in 70%, 77%, and 87

• % yield, respectively. The related reaction is also carried out with amides of non-pyridine derivatives terephthal- and benzamides to afford multiply fused heterocyclic compounds in 81% and 89% yields, respectively. Keywords: intramolecular C–H arylation; multiply fused heterocycles; palladium acetate

• ; phosphine ligand; pyridine amides; Introduction Transition-metal-catalyzed synthetic reactions have recently attracted much attention in synthetic organic chemistry [1][2]. C–H Arylation reactions catalyzed by a transition metal are of particular interest because these reactions involve rather superior

Synthesis of 2H-azirine-2,2-dicarboxylic acids and their derivatives

• Anastasiya V. Agafonova,
• Mikhail S. Novikov and
• Alexander F. Khlebnikov

Beilstein J. Org. Chem. 2024, 20, 3191–3197, doi:10.3762/bjoc.20.264

• their amides, esters, and azides by FeCl2-catalyzed isomerization of 3-aryl-5-chloroisoxazole-4-carbonyl chlorides into 3-aryl-2H-azirine-2,2-dicarbonyl dichlorides followed by their reaction with nucleophiles are reported. Two approaches to the preparation of 3-aryl-5-chloroisoxazole-4-carbonyl

• -ylcarbonyl)-2H-azirines, 1-(2H-azirine-2-carbonyl)benzotriazoles, 2H-azirine-2-carbonyl azides, anhydrides, amides, esters, and thioesters of azirine carboxylic acids, as well as azirine carboxylic acids themselves, have been prepared over the last decade (see [2] and references therein). Azirine-2

• reaction conditions for the preparation of amides from azirine-2-carbonyl chlorides [27] are not suitable for obtaining bis-amides from azirine-2,2-dicarbonyl dichlorides. In order to obtain a maximum yield, it is better in this case, to carry out the reaction with 2 equiv of the amine in the presence of 4

Advances in radical peroxidation with hydroperoxides

• Oleg V. Bityukov,
• Pavel Yu. Serdyuchenko,
• Andrey S. Kirillov,
• Gennady I. Nikishin,
• Vera A. Vil’ and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2024, 20, 2959–3006, doi:10.3762/bjoc.20.249

• catalytic system based on ruthenium salts [72][73]. The C(sp3)–H bond at the amides 76 was functionalized with the tert-butylperoxy radical under the action of the TBAI/TBHP system (Scheme 27) [74]. The target amido-peroxides 77 were synthesized in high yields. The authors proposed that the process begins

gem-Difluorovinyl and trifluorovinyl Michael acceptors in the synthesis of α,β-unsaturated fluorinated and nonfluorinated amides

• Monika Bilska-Markowska,
• Marcin Kaźmierczak,
• Wojciech Jankowski and
• Marcin Hoffmann

Beilstein J. Org. Chem. 2024, 20, 2946–2953, doi:10.3762/bjoc.20.247

• series of new α,β-unsaturated amides, both fluorinated and nonfluorinated, were synthesized. Keywords: gem-difluorovinyl Michael acceptors; Michael addition; trifluorovinyl Michael acceptors; α,β-unsaturated amides; Introduction The Michael reaction, characterized by the addition of stable carbon

• our laboratory, we have explored the synthesis of 3,3,3-trifluoro- and 2,3,3,3-tetrafluoro-N-substituted propanamides, contributing to the field of fluorinated amides [25]. We have also investigated deprotonation at the α position of other fluorinated carbonyl derivatives as a route to new building

• using organolithium reagents (Scheme 1), revealing new avenues in fluorinated unsaturated amide synthesis, which are present in numerous natural products, pharmaceuticals, and polymers [34][35][36][37][38]. The obtained α,β-unsaturated amides may represent promising structural motifs for further

Recent advances in transition-metal-free arylation reactions involving hypervalent iodine salts

• Ritu Mamgain,
• Kokila Sakthivel and
• Fateh V. Singh

Beilstein J. Org. Chem. 2024, 20, 2891–2920, doi:10.3762/bjoc.20.243

• underscored by the successful conversion of various α,α-difluoromethyl ketone groups into corresponding esters, amides, and difluoromethyl groups [58]. In 2021, Nilova and colleagues outlined an approach for the synthesis of highly hindered 1,2,3,4-tetrasubstituted benzenoid rings 15 using arynes generated

• -arylation of N-alkoxybenzamides 81 in absence of metal catalsyt at low temperatures [85]. The reaction resulted in the two products O-arylated 83 and N-arylated 84 amides (Scheme 33). By reacting various substituted diaryliodonium salts and the amide it was concluded that the chemoselectivity between O- and

Synthesis of tricarbonylated propargylamine and conversion to 2,5-disubstituted oxazole-4-carboxylates

• Kento Iwai,
• Akari Hikasa,
• Kotaro Yoshioka,
• Shinki Tani,
• Kazuto Umezu and
• Nagatoshi Nishiwaki

Beilstein J. Org. Chem. 2024, 20, 2827–2833, doi:10.3762/bjoc.20.238

• derivative has been employed (Scheme 1) [13][14]. Recently, we have demonstrated that the central carbonyl group of DEMO is highly electrophilic, facilitating the nucleophilic addition of less reactive reagents such as acid amides [23][24][25][26]. When the reaction was conducted in the presence of acetic

• amount of ammonium acetate and extending the reaction time (Table 4, entries 2 and 3). Conclusion N,O-Acetals 1, derived from DEMO and acid amides, reacted with lithium acetylide to afford the corresponding adduct 4 through highly electrophilic NAIs. The N-acyl and alkynyl groups could be modified using

• acid amides and acetylides, respectively. When adduct 4 was treated with a base or ammonium acetate, ring closure proceeded to form a five-membered ring, accompanied by the elimination of the ethoxycarbonyl group. 2,5-Disubstituted oxazole-4-carboxylic acid derivatives are frequently found in

Access to optically active tetrafluoroethylenated amines based on [1,3]-proton shift reaction

• Yuta Kabumoto,
• Eiichiro Yoshimoto,
• Bing Xiaohuan,
• Masato Morita,
• Motohiro Yasui,
• Shigeyuki Yamada and
• Tsutomu Konno

Beilstein J. Org. Chem. 2024, 20, 2776–2783, doi:10.3762/bjoc.20.233

• amides in moderate three-step yields. Keywords: amine; chirality transfer; [1,3]-proton shift reaction; tetrafluoroethylene fragment; Introduction A fluorine atom has quite peculiar chemical and physical properties compared to others, and hence changes in molecular properties resulting from the

• (R)-16 (Scheme 5). When the substituent R is an aromatic ring substituted by a halogen such as chlorine and bromine atoms, the amides (S)-23 were obtained in 22–27% yield and with very high optical purity ((S)-23b, (S)-23c), although as for (S)-23a, a satisfactory result (92% ee) could be obtained

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

• -hexadecylglycerol, as well as other common long-chain alcohols and amides. Although a general defensive function has been proposed for snake abdominal scent glands, the specific chemistry and moderate amounts of acids reported here may suggest a function in chemical signaling for the Mangshan pit viper. In addition

• , including piperidone [10], amines [5][10], and amides [3][5][10] have been also observed in certain species. The analyses of SGS in vipers (Viperidae) focused on New World pit vipers (Crotalinae). Early analyses of SGS lipids by thin-layer chromatography (TLC) [14], indicated that two pit vipers, the Timber

• 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

Base-promoted cascade recyclization of allomaltol derivatives containing an amide fragment into substituted 3-(1-hydroxyethylidene)tetronic acids

• Andrey N. Komogortsev,
• Constantine V. Milyutin and
• Boris V. Lichitsky

Beilstein J. Org. Chem. 2024, 20, 2585–2591, doi:10.3762/bjoc.20.217

• was isolated in unchanged form. It should be mentioned that the key step of the studied recyclization is an intramolecular nucleophilic addition of a nitrogen atom at the double bond of the pyranone ring. Comparing the chemical properties of the considered amides and hydrazides it can be assumed that

• aliphatic substituents at the ring nitrogen atom. Besides that, we managed to perform the investigated reaction using the corresponding aniline derivative 4r. It should be mentioned that in this case the considered recyclization proceeded in lower yield comparing with other amides and was accompanied by

A review of recent advances in electrochemical and photoelectrochemical late-stage functionalization classified by anodic oxidation, cathodic reduction, and paired electrolysis

• Nian Li,
• Ruzal Sitdikov,
• Ajit Prabhakar Kale,
• Joost Steverlynck,
• Bo Li and
• Magnus Rueping

Beilstein J. Org. Chem. 2024, 20, 2500–2566, doi:10.3762/bjoc.20.214

• > secondary. Functional groups such as silyloxy, amides, ethers, esters, enolizable ketones, and nitriles were found to be compatible with this transformation. Late-stage functionalization of different molecules was demonstrated; for example, the azidation of ibuprofen occurred preferentially at the secondary

Photoredox-catalyzed intramolecular nucleophilic amidation of alkenes with β-lactams

• Valentina Giraldi,
• Giandomenico Magagnano,
• Daria Giacomini,
• Pier Giorgio Cozzi and
• Andrea Gualandi

Beilstein J. Org. Chem. 2024, 20, 2461–2468, doi:10.3762/bjoc.20.210

• , Via Gobetti 85, 40129 Bologna, Italy 10.3762/bjoc.20.210 Abstract The direct nucleophilic addition of amides to unfunctionalized alkenes via photoredox catalysis represents a facile approach towards functionalized alkylamides. Unfortunately, the scarce nucleophilicity of amides and competitive side

• the linked alkene moiety, followed by hydrogen transfer from the hydrogen atom transfer (HAT) catalyst. This process was used to successfully prepare 2-alkylated clavam derivatives. Keywords: β-lactam; acridinium photocatalyst; alkenes; amides; intramolecular radical reaction; photoredox catalysis

• research [11][12], particularly focusing on innovative approaches to synthesize natural or bioactive compounds [13]. In the carboamination of alkenes, amides are used in photoredox cyclizations under proton-coupled electron transfer (PCET) conditions [14][15][16][17]. An alternative method to generate N

Asymmetric organocatalytic synthesis of chiral homoallylic amines

• Nikolay S. Kondratyev and
• Andrei V. Malkov

Beilstein J. Org. Chem. 2024, 20, 2349–2377, doi:10.3762/bjoc.20.201

• (R)-VANOL ligand 115 was attained by column chromatography in 92%. In 2015, further development of the 2-aza-Cope rearrangement strategy was reported by Johnson [43]. This work expanded the scope of the reaction to β-formyl amides 119 under the conditions of dynamic kinetic resolution (DKR) by

• , creating the desired syn-(2R,3S)-homoallylic amine 120 in high diastereo- and enantioselectivity. The reaction was tested with various aryl, benzyl, allyl, and alkyl-functionalised β-formyl N-morpholinyl amides 119; the amide function was also varied. Yields were scattered across the 31–90% range, with the

• (125) amides produced the corresponding homoallylic amines 126–130 with dr ≥ 9:1. In the case of R = Bn, all these amides showed yields greater 85% and ees above 86% for the unsubstituted allyl group transfer (126–129). The reaction showed low tolerance to changes in the allyl fragment: with a

Tandem diazotization/cyclization approach for the synthesis of a fused 1,2,3-triazinone-furazan/furoxan heterocyclic system

• Yuri A. Sidunets,
• Valeriya G. Melekhina and
• Leonid L. Fershtat

Beilstein J. Org. Chem. 2024, 20, 2342–2348, doi:10.3762/bjoc.20.200

• a 1,2,3-triazin-4-one core. The proposed method is based on tandem diazotization/azo coupling reactions of the corresponding amides (Scheme 1). In addition, application perspectives of thus prepared heterocyclic entities as thermally stable components of functional organic materials or NO-donor drug

• extended this approach to amides 5 containing a furazan ring that were obtained via the reaction of readily available 4-amino-3-furazancarboxylic acid 6 with various amines using 2-(1H-benzotriazole-1-yl)-1,1,3,3-tetramethylaminium tetrafluoroborate (TBTU) as a coupling reagent (Scheme 3; see Supporting

• Information File 1 for details) [43]. As expected, amides 5 also undergo tandem diazotization/azo coupling reaction to form the target [1,2,5]oxadiazolo[3,4-d][1,2,3]triazin-7(6H)-ones 7. It should also be noted, that compounds 7 were obtained in similar yields as the corresponding furoxan analogues

Deuterated reagents in multicomponent reactions to afford deuterium-labeled products

• Kevin Schofield,
• Shayna Maddern,
• Yueteng Zhang,
• Grace E. Mastin,
• Rachel Knight,
• Wei Wang,
• James Galligan and
• Christopher Hulme

Beilstein J. Org. Chem. 2024, 20, 2270–2279, doi:10.3762/bjoc.20.195

• is comprised of reaction of an isonitrile, amine, and aldehyde/ketone, in the presence of phenylphosphinic acid (PPA), to give α-amino amides [35]. Examples of deuterated Ugi-3CR products are represented in Scheme 4. Like the Ugi 4-CR reaction, there was no deuterium scrambling in the Ugi 3-CR. Using

• the Passerini reaction [40][41][42][43] discovered 60 years prior to the Ugi reaction. It uses the reactivity of isocyanides, aldehydes, and carboxylic acids to yield α-acyloxy amides (Scheme 6). Six deuterated analogs are reported in good yield with no observation of deuterium scrambling. For the

Selective hydrolysis of α-oxo ketene N,S-acetals in water: switchable aqueous synthesis of β-keto thioesters and β-keto amides

• Haifeng Yu,
• Wanting Zhang,
• Xuejing Cui,
• Zida Liu,
• Xifu Zhang and
• Xiaobo Zhao

Beilstein J. Org. Chem. 2024, 20, 2225–2233, doi:10.3762/bjoc.20.190

• thioesters and β-keto amides is reported. In refluxing water, the hydrolysis reactions of α-oxo ketene N,S-acetals in the presence of 1.0 equiv of dodecylbenzenesulfonic acid effectively afforded β-keto thioesters in excellent yield, while β-keto amides were successfully obtained in excellent yield when the

• hydrolysis reactions were carried out in the presence of 3.0 equiv of NaOH. The green approach to β-keto thioesters and β-keto amides avoids the use of harmful organic solvents, thiols and thiolacetates as well as amines, which could result in serious environmental and safety issues. Keywords: α-oxo ketene

• structural characters and multiple good reactivities [1][2][3][4]. Both β-keto thioesters [5][6][7][8][9][10][11][12] and β-keto amides [13][14][15][16][17][18][19][20][21][22] have served as useful synthetic intermediates for the synthesis of a range of potent natural products. Therefore, much effort has

O,S,Se-containing Biginelli products based on cyclic β-ketosulfone and their postfunctionalization

• Kateryna V. Dil and
• Vitalii A. Palchykov

Beilstein J. Org. Chem. 2024, 20, 2143–2151, doi:10.3762/bjoc.20.184

• amides, coumarins, alicyclic ketones, β-ketophosphonates, α-nitroketones, curcumin, and barbituric acid derivatives [1][2][8][9]. We analyzed a number of Biginelli-type products and publications and concluded that Se-containing DHPMs among the rarest examples and, in addition to this, ketosulfones have

Access to 2-oxoazetidine-3-carboxylic acid derivatives via thermal microwave-assisted Wolff rearrangement of 3-diazotetramic acids in the presence of nucleophiles

• Ivan Lyutin,
• Vasilisa Krivovicheva,
• Grigory Kantin and
• Dmitry Dar’in

Beilstein J. Org. Chem. 2024, 20, 1894–1899, doi:10.3762/bjoc.20.164

• well as a wide range of nucleophiles provides access to a structural diversity of medically relevant 2-oxoazetidine-3-carboxylic acid amides and esters. Keywords: β-lactams; diazotetramic acids; nucleophiles; spirocycles; thermolysis; Wolff rearrangement; Introduction The importance of the β-lactam

• derivatives (mainly amides) exhibit various types of biological activity, among which the following can be highlighted: inhibition of β-lactamases [4][5], antitubercular properties [6], antiproliferative and antibacterial activity [7], herbicidal properties [8][9], inhibition of neutral amino acid transporter

• (SLC6A19) [10]. Hence, developing new synthetic methods to create structurally diverse 2-oxoazetidine-3-carboxylic acid derivatives is a highly valuable endeavour that could have a positive impact on future drug discovery. Most synthetic approaches to amides and esters of 2-oxoazetidine-3-carboxylic acids

Oxidative fluorination with Selectfluor: A convenient procedure for preparing hypervalent iodine(V) fluorides

• Samuel M. G. Dearman,
• Xiang Li,
• Yang Li,
• Kuldip Singh and
• Alison M. Stuart

Beilstein J. Org. Chem. 2024, 20, 1785–1793, doi:10.3762/bjoc.20.157

• ring to stabilise the iodine(V) centre. Both sidearms were also changed to amides because the NR group is a point of diversity which could be used to modulate the sterics and electronics of these novel hypervalent iodine(V) compounds. Initially, we applied Togni’s oxidative fluorination protocol to

• be the best reagent for preparing bicyclic iodine(V) difluoride 6, this route was first investigated for the oxidative fluorinations of hypervalent iodine(III) amides 11a and 11b (Scheme 3). Unfortunately, these reactions did not work and difluoro(aryl)-λ5-iodanes 7a and 7b were not produced. Togni’s

• protocol using TCCA (4 equivalents) and KF (6 equivalents) was then applied to both bicyclic iodine(III) amides 11a and 11b, but these reactions also failed to form either difluoroiodane 7a or 7b. Following the successful preparation and isolation of difluoroiodane 6, we investigated its ability to

Ugi bisamides based on pyrrolyl-β-chlorovinylaldehyde and their unusual transformations

• Alexander V. Tsygankov,
• Vladyslav O. Vereshchak,
• Tetiana O. Savluk,
• Serhiy M. Desenko,
• Valeriia V. Ananieva,
• Oleksandr V. Buravov,
• Yana I. Sakhno,
• Svitlana V. Shishkina and
• Valentyn A. Chebanov

Beilstein J. Org. Chem. 2024, 20, 1773–1784, doi:10.3762/bjoc.20.156

• prepared and characterized. Surprisingly, a well-documented approach to obtain peptide-containing carboxylic acids through acid hydrolysis of the convertible isocyanide moiety in the Ugi bisamides proceeded in an unexpected manner in our case, leading to the formation of derivatives of amides of

• the double bond are trans configured. To find out the patterns of the new reaction, we applied different conditions to a wider range of starting bisamides 5–8 (Table 2). As in the model reaction (Scheme 3), the main products of the transformation were the corresponding amides 10a–d (Table 2). In the

• of p-CF3-substituted aniline when synthesizing bisamide 6d. The yield of the amide 10c was about 8% and it was also the first to precipitate. In addition, it is worth mentioning that the corresponding amides 10 were observed in 1H NMR spectra and LC–MS analysis in many mother liquors after filtration

Syntheses and medicinal chemistry of spiro heterocyclic steroids

• Laura L. Romero-Hernández,
• Ana Isabel Ahuja-Casarín,
• Penélope Merino-Montiel,
• Sara Montiel-Smith,
• José Luis Vega-Báez and
• Jesús Sandoval-Ramírez

Beilstein J. Org. Chem. 2024, 20, 1713–1745, doi:10.3762/bjoc.20.152

• ester under basic conditions was carried out, followed by the transformation of the carboxyl group to the amides 165 and 166 by treatment with thionyl chloride and the corresponding amine. Tetraoxanes were obtained from ketones 163, 165, and 166 by a peroxyacylation reaction using an acidic hydrogen

• on normal human peripheral blood mononuclear cells (PBMC). In 2003, a direct transformation of tetraoxanes to amides via carboxylic acid was also reported by the same research group [68]. Some amides were synthesized using methyl glycinate, di-n-propylamine, and piperidine with significant

• gave a diastereomeric mixture. A final transformation into the corresponding carboxylic acids 171 and amides 172 was performed in short reaction times (Scheme 44). Steroidal tetraoxanes showed

Methyltransferases from RiPP pathways: shaping the landscape of natural product chemistry

• Maria-Paula Schröder,
• Isabel P.-M. Pfeiffer and
• Silja Mordhorst

Beilstein J. Org. Chem. 2024, 20, 1652–1670, doi:10.3762/bjoc.20.147

• occur at the N-terminal amide, the peptide backbone, as well as on amino acid side chain amides (Figure 1). While traditional synthesis of N-methylated peptides is challenging and time consuming, installation via RiPP maturases provides an easier, quicker, and greener approach to confer these attributes

• member of the channel-forming, cytotoxic proteusins. It is biosynthesised by Microvirgula aerodenitrificans. Like polytheonamide B, aeronamide A shows cytotoxic activity against HeLa cells, with an IC50 of 1.48 nM. AerE, the PoyE homologue, installs five methylations on the amides of Asn25, Asn31, Asn37