Scope of tetrazolo[1,5-a]quinoxalines in CuAAC reactions for the synthesis of triazoloquinoxalines, imidazoloquinoxalines, and rhenium complexes thereof

• Laura Holzhauer,
• Chloé Liagre,
• Olaf Fuhr,
• Nicole Jung and
• Stefan Bräse

Beilstein J. Org. Chem. 2022, 18, 1088–1099, doi:10.3762/bjoc.18.111

• formation from tetrazolo[1,5-a]quinoxalines 1 is still limited. Triazole-linked N-heterocycles like pyridotriazoles and quinolinotriazoles exert a variety of favorable biological properties like anticancer and antimicrobial activities as well as protein kinase inhibition [10][13][14][15]. Moreover, a vast

Facile and diastereoselective arylation of the privileged 1,4-dihydroisoquinolin-3(2H)-one scaffold

• Dmitry Dar’in,
• Grigory Kantin,
• Alexander Bunev and
• Mikhail Krasavin

Beilstein J. Org. Chem. 2022, 18, 1070–1078, doi:10.3762/bjoc.18.109

• receptors 1 [3], AChE and BACE-1 inhibitor 2 [4], inhibitor of oncogenic p53-MDM2 protein–protein interaction 3 [5], positive allosteric modulator of ionotropic glutamate receptor NMDA-1 4 [6], insulin-like growth factor 1 receptor inhibitor 5 [7], and metabotropic glutamate receptor 7 modulator 6 [8

• probe for protein–protein interactions, including oncogenic ones [26]. As the first step towards biological characterization of compounds 9, they were screened for cytotoxicity against the NCI-H460 lung carcinoma cell line. The most potent cytotoxic agent (9j) reduced the number of viable cells by >95

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

• Supporting Information File 1). They encode five genes that are also present in the biosynthetic gene clusters of valanimycin [19] and KA57-A [20]: the putative two-component flavin-dependent monooxygenase similar to VlmH/VlmR, the homologous protein of VlmA, and two additional hypothetical proteins similar

• suggest their participation in this step. Ady6 shows weak homology to DUF4260 (PF14079.9), a family of integral membrane proteins with unknown functions, while Ady8 is similar to the ferritin-like superfamily protein (IPR009078). Ady6/Ady8 are homologous to VlmO/VlmB and SRO_1835/SRO_1837 in the

• gene clusters from each group indicated that several protein families are frequently observed in the genome neighborhoods of specific “VlmA” groups, such as Ady1-like methyltransferases (PF04072), homologous pairs of VlmJ/VlmK-like exo-olefin-forming enzymes (PF19279/PF03972), seryl-tRNA synthetases

Isolation and biosynthesis of daturamycins from Streptomyces sp. KIB-H1544

• Yin Chen,
• Jinqiu Ren,
• Ruimin Yang,
• Jie Li,
• Sheng-Xiong Huang and
• Yijun Yan

Beilstein J. Org. Chem. 2022, 18, 1009–1016, doi:10.3762/bjoc.18.101

• , the DatA protein was expressed and purified (Figure 4B). Incubating DatA with substrate 7 and ATP resulted in a new product 8, which was confirmed by HRMS–ESI data (m/z 291.0663 [M − H]−, calcd for ([C18H12O4] − H)−, 291.0663) (Figure S22, Supporting Information File 1). The product was not present in

• the control reaction with boiled DatA protein (Figure 4B). Furthermore, we could not detect any other intermediates in the reaction mixture through MS analysis (Figure S23, Supporting Information File 1). These results suggested that DatA could not catalyze the formation of the cyclopentenone ring. It

• mM MgCl2. Double crossover mutants were selected based on the Kan-Apr and then confirmed by PCR using primers. Finally, the mutant strain S. sp. KIB-H1544-∆datA was generated (Table S2, Supporting Information File 1). Expression and purification of recombinant DatA and EchA protein The DNA fragment

Identification of the new prenyltransferase Ubi-297 from marine bacteria and elucidation of its substrate specificity

• Jamshid Amiri Moghaddam,
• Huijuan Guo,
• Karsten Willing,
• Thomas Wichard and
• Christine Beemelmanns

Beilstein J. Org. Chem. 2022, 18, 722–731, doi:10.3762/bjoc.18.72

• , and a TIM barrel protein (EboE) [28]. While prior studies suggested that the enzymatic reactions carried out by EboA-E include the prenylation of an undetermined substrate by eboC (UbiA-297 homologue) and modifications of a polyhydroxylated aromatic metabolite, the enzymatic reactions carried out by

• membrane fractions (Figure S2, Supporting Information File 1). However, purification of active Ptases failed despite testing different detergent-based purification protocols. Thus, we performed assays with crude protein fractions (1st membrane faction) and protein-enriched membrane fractions, which were

• the most favored substrate amongst the tested panel. Thus, we shortly investigated different reaction parameters using 8-HQA and FPP as substrates. First, we compared the enzyme activity of crude protein fractions directly obtained from cell lysate and enriched UbiA-297 fractions (Figure 6). As

Structural basis for endoperoxide-forming oxygenases

• Takahiro Mori and
• Ikuro Abe

Beilstein J. Org. Chem. 2022, 18, 707–721, doi:10.3762/bjoc.18.71

• that play important roles in antimalarial activity by damaging membranes, inhibiting nucleic acid and protein syntheses, and so on [8][9]. The best studied endoperoxide-containing compound is probably prostaglandin H2 (PGH2), the common precursor of biologically active prostanoids [10][11][12

• located on the protein surface and solvent-exposed, the distance between C21 of fumitremorgin B and the iron center is 4.6 Å and the hydroxy group of Tyr68 is near C26 of fumitremorgin B (Figure 3C). Moreover, Tyr68 is located close to C13 of fumitremorgin B, at a distance of 3.7 Å. The comparison between

Shift of the reaction equilibrium at high pressure in the continuous synthesis of neuraminic acid

• Jannis A. Reich,
• Miriam Aßmann,
• Kristin Hölting,
• Paul Bubenheim,
• Jürgen Kuballa and
• Andreas Liese

Beilstein J. Org. Chem. 2022, 18, 567–579, doi:10.3762/bjoc.18.59

• loading was quantified by analyzing the protein concentration before and after immobilization using the Bradford assay for protein quantification [29]. Screening experiments showed that both enzymes were successfully immobilized on the carriers (Figure 2). For the immobilized epimerase, a maximal loading

• collected for protein quantification. Afterwards, the carriers were washed twice with immobilization buffer containing 0.5 M NaCl 1:1 (w/v) and three times with immobilization buffer 1:1 (w/v). They were stored afterwards refrigerated at 6 °C. Activity assays To compare the activities of both enzymes, a

Unusual highly diastereoselective Rh(II)-catalyzed dimerization of 3-diazo-2-arylidenesuccinimides provides access to a new dibenzazulene scaffold

• Anastasia Vepreva,
• Alexander S. Bunev,
• Andrey Yu. Kudinov,
• Grigory Kantin,
• Mikhail Krasavin and
• Dmitry Dar’in

Beilstein J. Org. Chem. 2022, 18, 533–538, doi:10.3762/bjoc.18.55

• diastereomer 2a is indicative of a sequence of concerted processes with an unambiguous stereochemistry control at each step where stereogenic centers are formed. Dibenzoazulenodipyrroles 2 have a pronounced three-dimensional character which make this chemotype promising as probe for protein–protein

Tetraphenylethylene-embedded pillar[5]arene-based orthogonal self-assembly for efficient photocatalysis in water

• Zhihang Bai,
• Krishnasamy Velmurugan,
• Xueqi Tian,
• Minzan Zuo,
• Kaiya Wang and
• Xiao-Yu Hu

Beilstein J. Org. Chem. 2022, 18, 429–437, doi:10.3762/bjoc.18.45

• power factories, containing many manufacturing units called chloroplasts. Briefly, the antenna molecules capture the light energy by using protein–pigment complexes and transfer it to the specialized reaction centers via the FRET process, where the excited state energy is transferred into useable

Cs₂CO₃-Promoted reaction of tertiary bromopropargylic alcohols and phenols in DMF: a novel approach to α-phenoxyketones

• Ol'ga G. Volostnykh,
• Olesya A. Shemyakina,
• Anton V. Stepanov and
• Igor' A. Ushakov

Beilstein J. Org. Chem. 2022, 18, 420–428, doi:10.3762/bjoc.18.44

• ], amyloid-β protein production inhibitory [52], urease inhibitory [53], farnesyl transferase inhibitory (kurasoin A and B) [54][55], antitumor and antibacterial (doxorubicin, olivomycin A, chromomycin A3, carminomycin I, epothilones) [56][57][58] activities. Experimental General information 1Н and 13С NMR

Menadione: a platform and a target to valuable compounds synthesis

• Acácio S. de Souza,
• Ruan Carlos B. Ribeiro,
• Dora C. S. Costa,
• Fernanda P. Pauli,
• David R. Pinho,
• Matheus G. de Moraes,
• Fernando de C. da Silva,
• Luana da S. M. Forezi and
• Vitor F. Ferreira

Beilstein J. Org. Chem. 2022, 18, 381–419, doi:10.3762/bjoc.18.43

• epoxides are formed through oxidation reactions in vivo, that occur in protein processes dependent on vitamin K [96][97]. Dwyer and co-workers described a procedure using sugar-derived hydroperoxides for the synthesis of epoxides in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as base [98][99

Four bioactive new steroids from the soft coral Lobophytum pauciflorum collected in South China Sea

• Di Zhang,
• Zhe Wang,
• Xiao Han,
• Xiao-Lei Li,
• Zhong-Yu Lu,
• Bei-Bei Dou,
• Wen-Ze Zhang,
• Xu-Li Tang,
• Ping-Lin Li and
• Guo-Qiang Li

Beilstein J. Org. Chem. 2022, 18, 374–380, doi:10.3762/bjoc.18.42

• were cultivated by Qilu University of Technology (Jinan, China). Transgenic zebrafish [Tg: zlyz-EGFP and Tg (vegfr2: GFP)] expressing enhanced green fluorescent protein (EGFP) was used in this article. The conditions of the maintenance complied with guidelines of the Organization for Economic Co

Regioselectivity of the S_EAr-based cyclizations and S_EAr-terminated annulations of 3,5-unsubstituted, 4-substituted indoles

• Jonali Das and
• Sajal Kumar Das

Beilstein J. Org. Chem. 2022, 18, 293–302, doi:10.3762/bjoc.18.33

• stereochemistry in the Ir-catalyzed allylic substitution reactions. In 2016, Billingsley and co-workers disclosed the total synthesis of (−)-indolactam V (6), a nanomolar agonist of protein kinase C (Scheme 3) [12]. The authors applied an intramolecular SEAr reaction of 4-substituted indole derivative to

New efficient synthesis of polysubstituted 3,4-dihydroquinazolines and 4H-3,1-benzothiazines through a Passerini/Staudinger/aza-Wittig/addition/nucleophilic substitution sequence

• Long Zhao,
• Mao-Lin Yang,
• Min Liu and
• Ming-Wu Ding

Beilstein J. Org. Chem. 2022, 18, 286–292, doi:10.3762/bjoc.18.32

• protein cleaving enzyme 1 (BACE-1) inhibitive [6], and cholinesterase enzyme inhibitive activities [7]. The 3,4-dihydroquinazoline skeleton also exists in some natural products such as vasicine and vasicoline [8]. Some 4H-3,1-benzothiazine derivatives have also received attention due to their good

Anomeric 1,2,3-triazole-linked sialic acid derivatives show selective inhibition towards a bacterial neuraminidase over a trypanosome trans-sialidase

• Peterson de Andrade,
• Sanaz Ahmadipour and
• Robert A. Field

Beilstein J. Org. Chem. 2022, 18, 208–216, doi:10.3762/bjoc.18.24

• ). Incubation at 37 °C along with shaking (200 rpm) was continued until optical density (OD600) reached 0.6. Heterologous protein expression was induced by adding isopropyl β-ᴅ-1-thiogalactopyranoside (IPTG) to a final concentration of 1 mM and incubating for 4 hours at 30 °C with shaking (180 rpm). The cells

• . The recombinant protein was separated from cell debris by centrifugation (20,000g, 30 min). The supernatant was loaded to a 5 mL HisTrapTM HP column (GE healthcare) pre-equilibrated with buffer A (50 mM Tris-HCl, pH 8.0, 150 mM NaCl, 20 mM imidazole) and purified at 4 °C using an ÄKTA pure FPLC system

The role of chemistry in the success of oligonucleotides as therapeutics

• Pawan Kumar and
• Tom Brown

Beilstein J. Org. Chem. 2022, 18, 197–199, doi:10.3762/bjoc.18.22

• , both of them target mRNA to disrupt protein synthesis. In the following text we will refer both antisense oligonucleotides and siRNAs collectively as therapeutic oligonucleotides. More than 10 oligonucleotide drugs have received regulatory approval by the FDA and are now helping patients suffering from

Ready access to 7,8-dihydroindolo[2,3-d][1]benzazepine-6(5H)-one scaffold and analogues via early-stage Fischer ring-closure reaction

• Irina Kuznetcova,
• Felix Bacher,
• Daniel Vegh,
• Hsiang-Yu Chuang and
• Vladimir B. Arion

Beilstein J. Org. Chem. 2022, 18, 143–151, doi:10.3762/bjoc.18.15

• particular enzymes. Preliminary results indicate that scaffold C shows good affinity to proto-oncogene tyrosine-protein kinase Src, a well-known anticancer target [47], with IC50 = 0.26 µM and is a suitable candidate for further structural optimization. Paullone related indolobenzazepinone isomers. 7,12

Regioselective synthesis of methyl 5-(N-Boc-cycloaminyl)-1,2-oxazole-4-carboxylates as new amino acid-like building blocks

• Jolita Bruzgulienė,
• Greta Račkauskienė,
• Aurimas Bieliauskas,
• Vaida Milišiūnaitė,
• Miglė Dagilienė,
• Gita Matulevičiūtė,
• Vytas Martynaitis,
• Sonata Krikštolaitytė,
• Frank A. Sløk and
• Algirdas Šačkus

Beilstein J. Org. Chem. 2022, 18, 102–109, doi:10.3762/bjoc.18.11

• peptide-like structure. Heterocyclic amino acids and related compounds have been used to prepare synthetic DNA-encoded compound libraries for the discovery of small molecule protein ligands [23][24][25]. Recently, a highly specific and potent p38α kinase inhibitor containing a 3-amino-1-phenyl-1H-pyrazole

1,2-Naphthoquinone-4-sulfonic acid salts in organic synthesis

• Ruan Carlos B. Ribeiro,
• Patricia G. Ferreira,
• Amanda de A. Borges,
• Luana da S. M. Forezi,
• Fernando de Carvalho da Silva and
• Vitor F. Ferreira

Beilstein J. Org. Chem. 2022, 18, 53–69, doi:10.3762/bjoc.18.5

• evaluated against their antioxidant activity and exhibited promising activity. Protein tyrosine phosphatase 1B (PTP1B) is essential in the dephosphorylation of the activated insulin receptor, and inhibition of this enzyme would be an excellent strategy for the treatment of type 2 diabetes. Ahn and co

• -workers [82] synthesized and evaluated several 1,2-naphthoquinones substituted at position C4 with alkyl- or arylamino groups for their inhibition of the PTP1B protein. Furthermore, to discover new effective anti-inflammatory and analgesic agents, Gouda and co-workers [83] synthesized various compounds in

The enzyme mechanism of patchoulol synthase

• Houchao Xu,
• Bernd Goldfuss,
• Gregor Schnakenburg and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2022, 18, 13–24, doi:10.3762/bjoc.18.2

• reinvestigate the biosynthesis of patchoulol (3) the synthetic gene for patchoulol synthase from P. cablin was cloned and expressed in Escherichia coli [8]. The purified protein (Figure S1 in Supporting Information File 1) converted FPP into 3 as the main product, besides several side products (see Figure S2 in

Peptide stapling by late-stage Suzuki–Miyaura cross-coupling

• Hendrik Gruß,
• Rebecca C. Feiner,
• Ridhiwan Mseya,
• David C. Schröder,
• Michał Jewgiński,
• Kristian M. Müller,
• Rafał Latajka,
• Antoine Marion and
• Norbert Sewald

Beilstein J. Org. Chem. 2022, 18, 1–12, doi:10.3762/bjoc.18.1

• stapling techniques to stabilise α-helical secondary structure motifs of peptides led to the design of modulators of protein–protein interactions, which had been considered undruggable for a long time. We disclose a novel approach towards peptide stapling utilising macrocyclisation by late-stage Suzuki

• + 7 for two helix turns, respectively, followed by Ru-catalysed cross-linking [7]. By this robust and reliable approach, a library of stapled peptides was generated influencing diverse α-helical dominated protein–protein interactions (PPI) spanning pathways involved in cancer, infectious diseases

• 1% in proteins, but is highly conserved in binding sites on protein surfaces mediating PPI [43], it is an attractive target for the development of selective diversifications. C–H activation of the indole C2 position by Pd-catalysis allows both selective arylation [44][45][46][47][48] and formation

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

• days. Isolation of compounds 1–5 Compounds 1–5 were obtained from a culture fermented in A16 production medium with a composition of glucose 2%, Pharmamedia® (Traders Protein, Memphis, TN, USA) 1%, and CaCO3 0.5%. The pH of the medium was adjusted to 7.0 before autoclaving. At the end of fermentation

Iron-catalyzed domino coupling reactions of π-systems

• Austin Pounder and
• William Tam

Beilstein J. Org. Chem. 2021, 17, 2848–2893, doi:10.3762/bjoc.17.196

GlycoBioinformatics

• Kiyoko F. Aoki-Kinoshita,
• Frédérique Lisacek,
• Niclas Karlsson,
• Daniel Kolarich and
• Nicolle H. Packer

Beilstein J. Org. Chem. 2021, 17, 2726–2728, doi:10.3762/bjoc.17.184

• one of the authors of this article, Fadda, used glyco-adapted molecular dynamics to explain in a separate publication [4] how the COVID-19 spike protein recognition element requires N-linked glycosylation to be exposed. Another approach to understanding glyco-interactions is described in a review

• protein O-linked glycome based on the specificity of mammalian glycoenzymes, in order to generate a theoretical glycolipid glycome. One of the main tasks of glycobioinformatics is to convert analytical data obtained from biological samples (cell lysates, tissues, isolated proteins) into glycoscience

• transcription factors using next-generation sequencing expression data of glycoenzymes in cancer cell lines. The latter paper uses knowledge from current open access glycomic databases to curate and validate glycan structures reported on proteins in the Protein Data Bank (PDB) database. Overall, the wide

Synthesis of new bile acid-fused tetrazoles using the Schmidt reaction

• Dušan Đ. Škorić,
• Olivera R. Klisurić,
• Dimitar S. Jakimov,
• Marija N. Sakač and
• János J. Csanádi

Beilstein J. Org. Chem. 2021, 17, 2611–2620, doi:10.3762/bjoc.17.174

• solubilizers, bile acids are now recognized as metabolism regulators through specific receptors: farnesoid X receptor (FXR) and Takeda G protein receptor 5 (TGR5) [1][2][3]. Research efforts to find ligands for these receptors initiated several synthetic studies where bile acids are being used as a starting