Structure and conformational analysis of spiroketals from 6-O-methyl-9(E)-hydroxyiminoerythronolide A

• Ana Čikoš,
• Irena Ćaleta,
• Dinko Žiher,
• Mark B. Vine,
• Ivaylo J. Elenkov,
• Marko Dukši,
• Dubravka Gembarovski,
• Marina Ilijaš,
• Snježana Dragojević,
• Ivica Malnar and
• Sulejman Alihodžić

Beilstein J. Org. Chem. 2015, 11, 1447–1457, doi:10.3762/bjoc.11.157

• sponges, which display extraordinary antitumor activity [29]. At the same time, the spiroketal-containing integramycin acts as an HIV-1 protease inhibitor [27]. The studies of Hayashi et al. have shown that the integrity of the spiroketal subunit is essential for the inhibition of telomerase by

C-5’-Triazolyl-2’-oxa-3’-aza-4’a-carbanucleosides: Synthesis and biological evaluation

• Roberto Romeo,
• Caterina Carnovale,
• Salvatore V. Giofrè,
• Maria A. Chiacchio,
• Adriana Garozzo,
• Emanuele Amata,
• Giovanni Romeo and
• Ugo Chiacchio

Beilstein J. Org. Chem. 2015, 11, 328–334, doi:10.3762/bjoc.11.38

• by exploiting a click chemistry reaction of 5’-azido-2’-oxa-3’-aza-4’a-carbanucleosides with substituted alkynes. Biological tests indicate an antitumor activity for the synthesized compounds: most of them inhibit cell proliferation of Vero, BS-C-1, HEp-2, MDCK, and HFF cells with a CC50 in the range

• of 5.0–40 μM. The synthesized compounds do not show any antiviral activity. Keywords: antitumor activity; click chemistry; 1,3-dipolar cycloaddition; nucleic acids; 2’-oxa-3’-aza-4’a-carbanucleoside analogs; Introduction Synthetic modified nucleosides are of great interest as potential new lead

• -carbanucleoside. However, in order to maintain the six-bond periodicity of the oligonucleotides and thus the flexibility of the oligonucleotide chain the methylene bridge at the pseudo-5’-position was retained. The obtained compounds have shown to be endowed with an interesting antitumor activity: most of them

Come-back of phenanthridine and phenanthridinium derivatives in the 21st century

• Lidija-Marija Tumir,
• Marijana Radić Stojković and
• Ivo Piantanida

Beilstein J. Org. Chem. 2014, 10, 2930–2954, doi:10.3762/bjoc.10.312

• (propidium iodide) as a probe for cell viability. Besides, an antiparasitic activity for EB was reported and it possesses significant antitumor activity [2][3][4][5] both in vivo and in vitro. Nevertheless, phenanthridine derivatives were rather neglected regarding their human medicinal applications due to

Photo, thermal and chemical degradation of riboflavin

• Muhammad Ali Sheraz,
• Sadia Hafeez Kazi,
• Sofia Ahmed,
• Zubair Anwar and
• Iqbal Ahmad

Beilstein J. Org. Chem. 2014, 10, 1999–2012, doi:10.3762/bjoc.10.208

• RF and β-cyclodextrin or hydroxypropyl-β-cyclodextrin at low concentrations occurred through hydrogen bonding and resulted in a better solubility of RF along with an enhanced antitumor activity [117]. On the contrary, the formation of inclusion complexes between RF and hydroxypropylated α-, β-, and γ

Multicomponent reactions in nucleoside chemistry

• Mariola Koszytkowska-Stawińska and
• Włodzimierz Buchowicz

Beilstein J. Org. Chem. 2014, 10, 1706–1732, doi:10.3762/bjoc.10.179

• afforded the Mannich base 12 in 81% yield. The deprotection of compound 12 with tetrabutylammonium fluoride gave the final product 13. Compound 13 showed antitumor activity (IC50 = 75 µM) against RDM4 tumor cells. Examples of the Mannich reaction employing a nucleoside as the aldehyde-bearing component are

Design, automated synthesis and immunological evaluation of NOD2-ligand–antigen conjugates

• Marian M. J. H. P. Willems,
• Gijs G. Zom,
• Nico Meeuwenoord,
• Ferry A. Ossendorp,
• Herman S. Overkleeft,
• Gijsbert A. van der Marel,
• Jeroen D. C. Codée and
• Dmitri V. Filippov

Beilstein J. Org. Chem. 2014, 10, 1445–1453, doi:10.3762/bjoc.10.148

• locus, which not only showed antitumor activity but also immunostimulatory effects [35]. Also, the commercially available immunomodulator Murabutide, a glutamine n-butyl ester derivative of MDP, supports the notion that modifications on the isoglutamine are allowed [36]. Thus, MDP-antigen conjugates 2–5

Cyclization–endoperoxidation cascade reactions of dienes mediated by a pyrylium photoredox catalyst

• Nathan J. Gesmundo and
• David A. Nicewicz

Beilstein J. Org. Chem. 2014, 10, 1272–1281, doi:10.3762/bjoc.10.128

• bond engenders these compounds with a range of important biological functions, most notably, antimalarial and antitumor activity (e.g., artemisinin, yingzhaosu A and merulin C) [1][2][3][4]. From a synthetic standpoint, the installation of the endoperoxide moiety presents a significant challenge due to

Consecutive isocyanide-based multicomponent reactions: synthesis of cyclic pentadepsipeptoids

• Angélica de Fátima S. Barreto,
• Otilie E. Vercillo,
• Ludger A. Wessjohann and
• Carlos Kleber Z. Andrade

Beilstein J. Org. Chem. 2014, 10, 1017–1022, doi:10.3762/bjoc.10.101

• cyclic depsipeptide is sansalvamide A (San A, Figure 1) [20][21][22][23][24][25][26][27][28][29], which was isolated from a marine fungus (Fusarium spp.) [20] and exhibits antitumor activity against multiple cancer cell lines. It is cytotoxic against colon (HCT-116) [20][23][25][26], pancreatic (S2-013

Isocyanide-based multicomponent reactions towards cyclic constrained peptidomimetics

• Gijs Koopmanschap,
• Eelco Ruijter and
• Romano V.A. Orru

Beilstein J. Org. Chem. 2014, 10, 544–598, doi:10.3762/bjoc.10.50

• naturally occurring cyclic peptides containing a six-membered core ringsystem. Such DKPs were shown to possess several interesting medicinally relevant properties such as antifungal [133][134], antibacterial [135], and antitumor activity [136][137] but are also used to introduce for example a bitter taste

Synthesis of five- and six-membered cyclic organic peroxides: Key transformations into peroxide ring-retaining products

• Alexander O. Terent'ev,
• Dmitry A. Borisov,
• Vera A. Vil’ and
• Valery M. Dembitsky

Beilstein J. Org. Chem. 2014, 10, 34–114, doi:10.3762/bjoc.10.6

• is one of the most widespread helminthic diseases; 800 million people are at risk of acquiring this infection [160][161][162][163][164][165][166][167][168][169][170][171][172][173][174]. Additionally, based on synthetic peroxides, several compounds exhibiting antitumor activity were synthesized

• synthesized by the oxidation of triterpenes 149a–d with Na2Cr2O7/N-hydroxysuccinimide (Scheme 36). The resulting compounds exhibit antitumor activity comparable with that of betulinic acid [175][176][177]. 1.6. Structural modifications, in which the 1,2-dioxolane ring remains intact The possibility of

Synthesis and characterization of novel bioactive 1,2,4-oxadiazole natural product analogs bearing the N-phenylmaleimide and N-phenylsuccinimide moieties

• Catalin V. Maftei,
• Elena Fodor,
• Peter G. Jones,
• M. Heiko Franz,
• Gerhard Kelter,
• Heiner Fiebig and
• Ion Neda

Beilstein J. Org. Chem. 2013, 9, 2202–2215, doi:10.3762/bjoc.9.259

• analogs 4 and 7 were then tested for antitumor activity toward a panel of 11 cell lines in vitro by using a monolayer cell-survival and proliferation assay. Compound 7 was the most potent and exhibited a mean IC50 value of approximately 9.4 µM. Aniline 1 was synthesized by two routes in one-pot reactions

• starting from tert-butylamidoxime and 4-aminobenzoic acid or 4-nitrobenzonitrile. The structures of compounds 1, 2, 4, 5 and 6 were confirmed by X-ray crystallography. Keywords: antitumor activity; bioisosteres; maleimide; natural product analogs; 1,2,4-oxadiazoles; Introduction The five-membered

• novel natural product analogs of 1,2,4-oxadiazole derivatives bearing N-phenylmaleimide or N-phenylsuccinimide functionalities in order to improve their biological activity. The new derivatives have been tested for in vitro antitumor activity toward a panel of 11 cell lines. Results and Discussion Clapp

Study on the total synthesis of velbanamine: Chemoselective dioxygenation of alkenes with PIFA via a stop-and-flow strategy

• Huili Liu,
• Kuan Zheng,
• Xiang Lu,
• Xiaoxia Wang and
• Ran Hong

Beilstein J. Org. Chem. 2013, 9, 983–990, doi:10.3762/bjoc.9.113

• synthetic chemists to develop novel strategies for their efficient synthesis [2][3][4][5][6][7][8][9][10][11]. Isolated from the pantropical plant Catharanthus roseus, vinblastine (3) and vincristine (4) have potent antitumor activity and are clinically utilized in the treatment of Hodgkin’s disease and

Synthesis of 2,3-dihydronaphtho[2,3-d][1,3]thiazole-4,9-diones and 2,3-dihydroanthra[2,3-d][1,3]thiazole-4,11-diones and novel ring contraction and fusion reaction of 3H-spiro[1,3-thiazole-2,1'-cyclohexanes] into 2,3,4,5-tetrahydro-1H-carbazole-6,11-diones

• Lidia S. Konstantinova,
• Kirill A. Lysov,
• Ljudmila I. Souvorova and
• Oleg A. Rakitin

Beilstein J. Org. Chem. 2013, 9, 577–584, doi:10.3762/bjoc.9.62

• heterocycles (pyrrole [6][7], and triazoles [8]) were found to possess antifungal and antitumor activity toward a number of species causing fungal diseases and toward Walker 256 carcinoma cell lines. The compounds with the thiazoloanthroquinone structure have not been reported in the literature so far. We were

First synthesis of 2-(benzofuran-2-yl)-6,7-methylene dioxyquinoline-3-carboxylic acid derivatives

• Wentao Gao,
• Jia Liu,
• Yun Jiang and
• Yang Li

Beilstein J. Org. Chem. 2011, 7, 210–217, doi:10.3762/bjoc.7.28

• intermediates which may be responsible for the observed antitumor activity of lignans [23][24]. The presence of the methylenedioxy moiety in some other bioactive molecules drastically alters their pharmacological properties. For example, among the tested 2-phenylquinolin-4-ones (2-PQs) with potent cytotoxicity

Functional properties of metallomesogens modulated by molecular and supramolecular exotic arrangements

• Alessandra Crispini,
• Mauro Ghedini and
• Daniela Pucci

Beilstein J. Org. Chem. 2009, 5, No. 54, doi:10.3762/bjoc.5.54

• multifunctional soft materials, with higher performance than classical liquid crystals. Our interest in the synthesis of metallomesogens and their wide use in the field of material science, coupled with the fact that transition metal complexes have potential antitumor activity, led us to believe that a great

Recent progress on the total synthesis of acetogenins from Annonaceae

• Nianguang Li,
• Zhihao Shi,
• Yuping Tang,
• Jianwei Chen and
• Xiang Li

Beilstein J. Org. Chem. 2008, 4, No. 48, doi:10.3762/bjoc.4.48

• synthesis of longicin In 1995, McLaughlin’group reported the isolation of longicin (101) from Asimina longifolia (Annonaceae). Longicin was reported to exhibit over 1 million-fold selective antitumor activity against PACA-2 (IC50 = 1.25 × 10−9 µg/mL) compared to adriamycin (IC50 = 1.95 × 10−3 µg/mL)[49]. In

Synthesis of crispine A analogues via an intramolecular Schmidt reaction

• Ajoy Kapat,
• Ponminor Senthil Kumar and
• Sundarababu Baskaran

Beilstein J. Org. Chem. 2007, 3, No. 49, doi:10.1186/1860-5397-3-49

• known as crispine A was isolated from Carduus crispus, a popular invasive plant occurring in Asia and Europe, which was found to exhibit superior antitumor activity against SKOV3, KB and HeLa human cancer lines.[19] As a result of its potent antitumor activity, various synthetic methods have been