Diosgenyl 2-amino-2-deoxy-β-D-galactopyranoside: synthesis, derivatives and antimicrobial activity

• Henryk Myszka,
• Patrycja Sokołowska,
• Agnieszka Cieślińska,
• Andrzej Nowacki,
• Maciej Jaśkiewicz,
• Wojciech Kamysz and
• Beata Liberek

Beilstein J. Org. Chem. 2017, 13, 2310–2315, doi:10.3762/bjoc.13.227

• /bjoc.13.227 Abstract The synthesis of diosgenyl 2-amino-2-deoxy-β-D-galactopyranoside is presented for the first time. This synthetic saponin was transformed into its hydrochloride as well as N-acyl, 2-ureido, N-alkyl, and N,N-dialkyl derivatives. Antifungal and antibacterial studies show that some of

• , particularly antifungal [3][4][5][6] and antitumor [7][8][9]. The aglycone part of a saponin is termed sapogenin. Diosgenin, yamogenin, tigogenin, smilagenin and sarsapogenin are the most abundant sapogenins in nature [10]. They are linked via a glycosidic bond to a sugar unit, mainly D-glucose. Diosgenyl

• diosgenyl saponins are used in folk medicine in many countries. Such herbal medicines exhibit anti-inflammatory, antibacterial, antifungal, antiviral, diuretic and expectorant activities [2][11]. Importantly, these also help fight cancer cells [12][13][14]. Although saponins, in which D-galactose is

Syntheses of 3,4- and 1,4-dihydroquinazolines from 2-aminobenzylamine

• Jimena E. Díaz,
• Silvia Ranieri,
• Nadia Gruber and
• Liliana R. Orelli

Beilstein J. Org. Chem. 2017, 13, 1470–1477, doi:10.3762/bjoc.13.145

• analogues, dihydroquinazolines, also represent heterocyclic cores of pharmacological interest. Some derivatives containing this motif have shown antimicrobial [11] and antifungal properties [12]. Their activity as selective T-type calcium channel blockers [13][14][15] and as inhibitors of β-secretase (an

Sustainable synthesis of 3-substituted phthalides via a catalytic one-pot cascade strategy from 2-formylbenzoic acid with β-keto acids in glycerol

• Lina Jia and
• Fuzhong Han

Beilstein J. Org. Chem. 2017, 13, 1425–1429, doi:10.3762/bjoc.13.139

• [3][4][5], exhibit a broad spectrum of pharmacological activity, such as antibacterial, anti-HIV, antifungal, antibiotic, antitumor and immunosuppressive effects [6][7][8][9][10]. In addition, the one-pot cascade transformation has proven to be the key step in organic syntheses because of its broad

Urea–hydrogen peroxide prompted the selective and controlled oxidation of thioglycosides into sulfoxides and sulfones

• Adesh Kumar Singh,
• Varsha Tiwari,
• Kunj Bihari Mishra,
• Surabhi Gupta and
• Jeyakumar Kandasamy

Beilstein J. Org. Chem. 2017, 13, 1139–1144, doi:10.3762/bjoc.13.113

• for the construction of highly functionalized natural products [1][2]. Sulfur moieties are found in several therapeutically important molecules that possess antibacterial, antifungal, anti-ulcer, anti-atherosclerotic, antihypertensive activities, etc. [3][4]. Sulfur compounds also play an important

Cycloheximide congeners produced by Streptomyces sp. SC0581 and photoinduced interconversion between (E)- and (Z)-2,3-dehydroanhydrocycloheximides

• Li Yang,
• Ping Wu,
• Jinghua Xue,
• Huitong Tan,
• Zheng Zhang and
• Xiaoyi Wei

Beilstein J. Org. Chem. 2017, 13, 1039–1049, doi:10.3762/bjoc.13.103

• 2 and 3 was observed and verified and the possible reaction path and mechanism were proposed by theoretical computations. The antifungal and cytotoxic activities of 1–6 were evaluated and suggested that 2,3-dehydrogenation results in the loss of the activities and supported that the OH-α is

• important to the activities of cycloheximide congeners. Keywords: antifungal activity; cycloheximide derivatives; E/Z photoisomerization; Streptomyces sp; theoretical conformational analysis; Introduction The glutarimide-containing antibiotics represent a fascinating class of natural products that exhibit

• without the toxic side-effects could provide a viable lead of therapeutic drugs or agricultural pesticides. During the course of our searching for bioactive microbial metabolites [8][9], a culture extract of Streptomyces sp. SC0581 was found to show antifungal activity against the phytopathogen

New approach toward the synthesis of deuterated pyrazolo[1,5-a]pyridines and 1,2,4-triazolo[1,5-a]pyridines

• Aleksey Yu. Vorob’ev,
• Vyacheslav I. Supranovich,
• Gennady I. Borodkin and
• Vyacheslav G. Shubin

Beilstein J. Org. Chem. 2017, 13, 800–805, doi:10.3762/bjoc.13.80

• treating asthma and post-stroke patients [16]. 1,2,4-Triazolo[1,5-a]pyridines show antifungal [17], antitumor [18], and cytotoxic [19] activities. Both types of heterocyclic cores are readily available from N-aminopyridium salts and related pyridinium-N-imines via 1,3-cycloaddition reaction [20] or

N-Propargylamines: versatile building blocks in the construction of thiazole cores

• S. Arshadi,
• E. Vessally,
• L. Edjlali,
• R. Hosseinzadeh-Khanmiri and
• E. Ghorbani-Kalhor

Beilstein J. Org. Chem. 2017, 13, 625–638, doi:10.3762/bjoc.13.61

• pharmacological activities. For example, abafungin (Figure 1) is an antifungal drug marketed worldwide for the treatment of dermatomycoses. It works by inhibiting the enzyme sterol 24-C-methyltransferase [1][2][3][4]. Febuxostat, also known by its brand name adenuric is a xanthine oxidase inhibitor that helps to

Synthesis of 1-indanones with a broad range of biological activity

• Marika Turek,
• Dorota Szczęsna,
• Marek Koprowski and
• Piotr Bałczewski

Beilstein J. Org. Chem. 2017, 13, 451–494, doi:10.3762/bjoc.13.48

• antibacterial activity against Escherichia coli and Bacillus subtilis, and antifungal activity against Aspergillus niger and Penicillium notatum. Among the synthesized series of 1-indanone derivatives 64, the highest antibacterial activity was exhibited by derivatives 64k and 64l, whereas the most potent

• antifungal activity was revealed for derivatives 64h and 64j. The authors have also studied anti-inflammatory properties of these derivatives using the carrageenan induced paw edema method in rats. The anti-inflammatory activity of the synthesized compounds was compared with standard indomethacin (a non

• antiviral and antifungal molecule produced by bacteria. Because of its interesting biological activity, Mitchell and Liebeskind have decided to synthesize abicoviromycin (168) derivatives [78]. In spite of the potent biological activity, abicoviromycin (168) is extremely heat- and acid-sensitive. Moreover

Biosynthetic origin of butyrolactol A, an antifungal polyketide produced by a marine-derived Streptomyces

• Enjuro Harunari,
• Hisayuki Komaki and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2017, 13, 441–450, doi:10.3762/bjoc.13.47

• , Kisarazu, Chiba 292-0818, Japan 10.3762/bjoc.13.47 Abstract Butyrolactol A is an antifungal polyketide of Streptomyces bearing an uncommon tert-butyl starter unit and a polyol system in which eight hydroxy/acyloxy carbons are contiguously connected. Except for its congener butyrolactol B, there exist no

• -like structures [4][5][6][7][8]. Butyrolactol A (1) is an antifungal polyketide first isolated from Streptomyces rochei S785-16 [9] (Figure 1). The left half of 1 is the hydrophobic unconjugated tetraene system including one Z-olefin with a terminal tert-butyl group, whereas the hydrophilic polyol

• structure and the antifungal potency, no further research has been reported for 1. There are two interesting aspects in the structure of butyrolactol A (1). First, among the polyketides, a tert-butyl group has been found exclusively in metabolites of marine cyanobacteria except for 1 [11][12][13][14

Brønsted acid-mediated cyclization–dehydrosulfonylation/reduction sequences: An easy access to pyrazinoisoquinolines and pyridopyrazines

• Ramana Sreenivasa Rao and
• Chinnasamy Ramaraj Ramanathan

Beilstein J. Org. Chem. 2017, 13, 428–440, doi:10.3762/bjoc.13.46

• anticancer [2][3], antifungal [4], amoebiasis, trypanosomiasis, bilharziasis [5][6], and schistosomiasis [7][8]. Some are cell adhesion inhibitors [9] brandykinin receptor antagonists [10][11] and chymase inhibitors [12]. Quinoxaline derivatives are known to act as aldose reductase (ALR2) inhibitors and are

Computational methods in drug discovery

• Sumudu P. Leelananda and
• Steffen Lindert

Beilstein J. Org. Chem. 2016, 12, 2694–2718, doi:10.3762/bjoc.12.267

Selective synthesis of thioethers in the presence of a transition-metal-free solid Lewis acid

• Federica Santoro,
• Matteo Mariani,
• Federica Zaccheria,
• Rinaldo Psaro and
• Nicoletta Ravasio

Beilstein J. Org. Chem. 2016, 12, 2627–2635, doi:10.3762/bjoc.12.259

• are a very important field of research as traditional coupling methods, although they proved effective in industrial applications, generate harmful metal waste and many byproducts [3]. Thioethers are important building blocks for the synthesis of antibacterial and antifungal agents [4][5] and as

Selective and eco-friendly procedures for the synthesis of benzimidazole derivatives. The role of the Er(OTf)₃ catalyst in the reaction selectivity

• Natividad Herrera Cano,
• Jorge G. Uranga,
• Mónica Nardi,
• Antonio Procopio,
• Daniel A. Wunderlin and
• Ana N. Santiago

Beilstein J. Org. Chem. 2016, 12, 2410–2419, doi:10.3762/bjoc.12.235

• ][7] or benzothiazole [8][9] rings in numerous compounds is an important structural element for their biological and medical applications. For example benzimidazoles are widely spread in antiulcer, antihypertensive, antiviral, antifungal, anticancer, and antihistaminic medicines, among others [10][11

An effective one-pot access to polynuclear dispiroheterocyclic structures comprising pyrrolidinyloxindole and imidazothiazolotriazine moieties via a 1,3-dipolar cycloaddition strategy

• Alexei N. Izmest’ev,
• Galina A. Gazieva,
• Natalya V. Sigay,
• Sergei A. Serkov,
• Valentina A. Karnoukhova,
• Vadim V. Kachala,
• Alexander S. Shashkov,
• Igor E. Zanin,
• Angelina N. Kravchenko and
• Nina N. Makhova

Beilstein J. Org. Chem. 2016, 12, 2240–2249, doi:10.3762/bjoc.12.216

• viruses [35], anti-HIV and anticancer [36][37], antimicrobial and antifungal activities as well as cytotoxicity to MCF-7 cells [38][39]. Based on these observations we therefore aimed at combining the spiropyrrolidinyloxindole motif with hetero-annelated 1,2,4-triazine scaffolds. Recently, we have already

Evidence for an iterative module in chain elongation on the azalomycin polyketide synthase

• Hui Hong,
• Yuhui Sun,
• Yongjun Zhou,
• Emily Stephens,
• Markiyan Samborskyy and
• Peter F. Leadlay

Beilstein J. Org. Chem. 2016, 12, 2164–2172, doi:10.3762/bjoc.12.206

• polyketide. Two of these are the near-identical PKSs (Figure S1, Supporting Information File 1) for the antifungal 36-membered marginolactones azalomycin 1a–c (from Streptomyces malaysiensis (formerly Streptomyces violaceusniger) DSM4137) and kanchanamycin 1d [35][36] from Streptomyces olivaceus Tü4018; and

Synthesis of the C8’-epimeric thymine pyranosyl amino acid core of amipurimycin

• Pramod R. Markad,
• Navanath Kumbhar and
• Dilip D. Dhavale

Beilstein J. Org. Chem. 2016, 12, 1765–1771, doi:10.3762/bjoc.12.165

• , antiviral, antibacterial and antifungal [2]. Peptidyl nucleosides in which the sugar part is in the furanose form are common, however, the sugar framework in the pyranose form, with a nucleobase and a peptide linker at either ends, are rare in nature. A few examples of this category are amipurimycin and

• miharamycin that are known as antifungal agents [2]. Amipurimycin (1) isolated from Streptomyces novoguineensis sp. nov., displays antifungal activity against pyricularia oryzae – a causative agent in rice blast disease [3][4]. Goto and co-workers have proposed the primary structure of amipurimycin (1, Figure

• configurations at the C6’, C2” and C3” of the cis-pentacin are still undefined. Thus, the partially unresolved structure, a potent antifungal activity, the unexplored mode of action and the limited synthetic study make amipurimycin (1) an attractive target for futher investigation. As of now, a total synthesis

Rearrangements of organic peroxides and related processes

• Ivan A. Yaremenko,
• Vera A. Vil’,
• Dmitry V. Demchuk and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2016, 12, 1647–1748, doi:10.3762/bjoc.12.162

• activities, including antibacterial, antiviral, antifungal, anti-allergic, anti-oxidant, and anti-inflammatory [348][349]. The treatment of endoperoxide 238 with Et3N gave 1,4-diketone 240 in quantitative yield instead of expected hydroxy ketone 239 (Scheme 73) [350][351][352]. The endoperoxide 238 is

Total synthesis of leopolic acid A, a natural 2,3-pyrrolidinedione with antimicrobial activity

• Atul A. Dhavan,
• Rahul D. Kaduskar,
• Loana Musso,
• Leonardo Scaglioni,
• Piera Anna Martino and
• Sabrina Dallavalle

Beilstein J. Org. Chem. 2016, 12, 1624–1628, doi:10.3762/bjoc.12.159

• residue, which in turn, is connected to the ureido dipeptide L-Phe-L-Val. The compound showed antifungal and antibacterial activity against Mucor hiemalis and Staphylococcus aureus with a MIC of 32 and 16 μg/mL, respectively [2]. Compounds containing the isomeric 2,4-pyrrolidinedione ring system (tetramic

• acids) are widespread among the fungal metabolites and show a number of biological activities, i.e., antibacterial, antiviral, antifungal and anticancer. More than one hundred of them have been isolated from a variety of natural sources [3]. Conversely, natural compounds with a simple 2,3

Biosynthesis of oxygen and nitrogen-containing heterocycles in polyketides

• Franziska Hemmerling and
• Frank Hahn

Beilstein J. Org. Chem. 2016, 12, 1512–1550, doi:10.3762/bjoc.12.148

• polyketide with potent antitumor, antifungal, antiparasitic, pesticidal and antitrypanosomal activities (Scheme 13). In its biosynthesis, the furan-ring formation occurs on a late stage, catalysed in an unprecedented fashion by the cytochrome P450 oxidase AurH [13][62][63][64][65][66][67]. This enzyme

Mutagenic activity of quaternary ammonium salt derivatives of carbohydrates

• Barbara Dmochowska,
• Karol Sikora,
• Anna Woziwodzka,
• Jacek Piosik and
• Beata Podgórska

Beilstein J. Org. Chem. 2016, 12, 1434–1439, doi:10.3762/bjoc.12.138

• their usage reaches hundreds of thousands of tons every year – in 2004 that number reached 0.5 million tons [6]. Antibacterial and antifungal action is the significant property of QAS. Therefore, they are being used as disinfectants, starting from hospital services to wood protection and house

• [22][23][24]. To overcome many problems associated with QASs, they were combined with sugars. We intended to obtain biologically active compounds – especially antibacterial and antifungal – with high biocompatibility and good biodegradation properties. Some examples of fused molecules containing QASs

Modular synthesis of the pyrimidine core of the manzacidins by divergent Tsuji–Trost coupling

• Sebastian Bretzke,
• Stephan Scheeff,
• Felicitas Vollmeyer,
• Friederike Eberhagen,
• Frank Rominger and
• Dirk Menche

Beilstein J. Org. Chem. 2016, 12, 1111–1121, doi:10.3762/bjoc.12.107

• last century [2]. The compounds have demonstrated potent antifungal activity [3], and acted as α-adrenoceptor blockers, antagonists of the serotonergic receptor and/or actomyosin ATPase activators [23][24][25]. As shown in Figure 1 for the most prominent representatives, manzacidins A (1) and C (2

Antibacterial structure–activity relationship studies of several tricyclic sulfur-containing flavonoids

• Lucian G. Bahrin,
• Henning Hopf,
• Peter G. Jones,
• Laura G. Sarbu,
• Cornelia Babii,
• Alina C. Mihai,
• Marius Stefan and
• Lucian M. Birsa

Beilstein J. Org. Chem. 2016, 12, 1065–1071, doi:10.3762/bjoc.12.100

• display antibacterial, antiviral, antifungal, anti-inflammatory and anticancer properties [4][5][6][7][8][9][10]. Their polyphenolic structure also gives them excellent anti-oxidant and cardioprotective properties [11][12]. Our research group has recently reported the antibacterial properties of a new

Marine-derived myxobacteria of the suborder Nannocystineae: An underexplored source of structurally intriguing and biologically active metabolites

• Antonio Dávila-Céspedes,
• Peter Hufendiek,
• Max Crüsemann,
• Till F. Schäberle and
• Gabriele M. König

Beilstein J. Org. Chem. 2016, 12, 969–984, doi:10.3762/bjoc.12.96

• strain Na a174, is supposed to be a result of degradation processes due to long-time cultivation. Additionally, the known compound 1,6-dihydroxyphenazin (19) and its arabinofuranoside 20 were obtained. To date, 14 has shown marginal antifungal activity towards Mucor hiemalis (DSM 2656, MIC: 33.3 μg/mL

• flava (DSM 14601) as their closest relative (16S rDNA sequence identity lower than 95%). The GC content of H. ochraceum and H. tepidum is 67 and 69 mol %, respectively. H. ochraceum was found by Fudou et al. [51] to be a producer of secondary metabolites with antibacterial and antifungal activities

• niger (AJ117374, MIC: 12.5 μg mL−1) and Fusarium sp. (AJ177167, MIC: 6.3 μg mL−1). These MIC values were in a similar range as those of known antifungal compounds such as amphotericin B or nystatin against the same fungi (MIC: 3.1 μg mL−1 for both compounds). Recently, the 9.4 Mb genome of H. ochraceum

A cross-metathesis approach to novel pantothenamide derivatives

• Jinming Guan,
• Matthew Hachey,
• Lekha Puri,
• Vanessa Howieson,
• Kevin J. Saliba and
• Karine Auclair

Beilstein J. Org. Chem. 2016, 12, 963–968, doi:10.3762/bjoc.12.95

• ]. One successful research direction has been to revisit “older” unexploited structural classes of antimicrobials [2][3][4][5]. As first demonstrated in the 1970s [6], many pantothenamides show antimicrobial activity [7][8][9][10][11][12], including antibacterial, antifungal and/or antiplasmodial

Antibiotics from predatory bacteria

• Juliane Korp,
• María S. Vela Gurovic and
• Markus Nett

Beilstein J. Org. Chem. 2016, 12, 594–607, doi:10.3762/bjoc.12.58

• , respectively. In contrast, the tripeptidic cystobactamid 507 seems to be either a biosynthetic byproduct or a degradation fragment of its larger congeners. All cystobactamids lack antifungal and cytotoxic properties, but they exhibit significant antibacterial activities. Especially derivative 919-2 (19