Synthesis of Novel Biphenyltetrazole Derivatives Containing 5‐Methylisoxazole Substituted 1,2,4‐Triazole

An efficient route to synthesize the target compounds was developed. Fifteen new 5‐[4′‐(5‐isoxazol‐4‐aryl‐1,2,4‐triazol‐3‐yl‐sulfanylmethyl)‐biphenyl‐2‐yl]‐tetrazoles derivatives were synthesized. The structures of the new compounds synthesized were confirmed by elemental analyses and spectral data.     

A New Pregnane and a New Diphenylmethane from the Root Barks of Periploca sepium

A new polyoxygenated pregnane genin and a new diphenylmethane, along with five known pregnane derivatives, were isolated from the root barks of Periploca sepium. The structures of the new compounds were elucidated as (3β,14β)‐3,14‐dihydroxy‐21‐methoxypregn‐5‐en‐20‐one ( 1 ) and 2‐hydroxy‐5‐(2‐hydroxy‐4‐methoxybenzyl)‐4‐methoxybenzaldehyde ( 2 ) on the basis of spectroscopic methods, especially 2D‐NMR and MS analyses. The known compounds were identified by comparing their physical and spectroscopic data with those reported in the literature.     

Indoloquinazoline Alkaloids from Araliopsis tabouensis

Three new indoloquinazolidine‐type alkaloids, 8,13‐dihydro‐2‐methoxyindolo[2′,3′: 3,4]pyrido[2,1‐b]quinazolin‐5(7H)‐one ( 1 ), 8,13‐dihydro‐2‐methoxy‐13‐methylindolo[2′,3′: 3,4]pyrido[2,1‐b]quinazolin‐5(7H)‐one ( 2 ), and 5,8,13,14‐tetrahydro‐2‐methoxy‐14‐methyl‐5‐oxo‐7H‐indolo[2′,3′: 3,4]pyrido[2,1‐b]quinazolim‐6‐iun chloride ( 3 ) were isolated from Araliopsis tabouensis, together with three known compounds. The structures of the new compounds were determined primarily from 1D‐ and 2D‐NMR analysis. The antimalarial activities of compounds 1 – 5 were evaluated against Plasmodium falciparum D6 and W2 clones. The IC₅₀ values in antimalarial bioassay for compounds 2 – 5 varied from 1.8 to 4.7 μg/ml.     

Synthesis of Polyfunctionally Substituted Fused Pyrimidine Derivatives as Antimicrobial Agents

A variety of pyrimidine derivatives 2—4 and annulated pyrimidine derivatives 5—17 have been synthesized via a sequence of heterocyclization reaction of readily available 6-naphthyl-4-oxo-2-thioxo-1,2,3,4-tetrahydroprimi-     

Bioactive Components from the Mycelium of Antrodia Salmonea

Three new compounds, 2,4‐dimethoxy‐6‐methylbenzene‐1,3‐diol ( 1 ), salmoquinone ( 2 ), and 3‐(4‐hydroxyphenyl)‐4‐isobutyl‐1H‐pyrrole‐2,5‐dione ( 3 ), together with six known compounds, 2‐methoxy‐6‐methyl‐p‐benzoquinone ( 4 ), 2,3‐dimethoxy‐5‐methyl‐p‐benzoquinone ( 5 ), 2‐hydroxy‐5‐methoxy‐3‐methyl‐p‐benzoquinone ( 6 ), eburcoic acid ( 7 ), fomefficinic acid C ( 8 ), and a pyrroledione ( 9 ), were isolated from the mycelium of Antrodia salmonea. The structures of these compounds were elucidated by spectrometric analyses including IR, NMR, and MS. Among these compounds, 4 and 5 exhibited cytotoxicity against KB, HepG2, and H2058 cell lines.     

Phenolic Compounds from Scorzonera tomentosa L.

From the subaerial parts of S. tomentosa L. (Asteraceae), two new dihydroisocoumarins, compounds 1 and 2 , a new phthalide, 3 , and a new stilbene derivative, 4 , were isolated, together with four known compounds, (±)‐hydrangenol ( 5 ), (?)‐hydrangenol 4′‐O‐β‐glucoside ( 6 ), (±)‐hydramacrophyllol A ( 7 ), and (±)‐hydramacrophyllol B ( 8 ). All secondary metabolites were identified on the basis of physicochemical, spectroscopic, and mass‐spectrometric data. The known compounds 5 – 8 were isolated for the first time from this species.     

Efficient Synthesis of New Benzofuran‐based Thiazoles and Investigation of their Cytotoxic Activity Against Human Breast Carcinoma Cell Lines

A new series of 1,3‐thiazole‐benzofuran derivatives was synthesized via heterocyclization of 2‐(1‐(6‐alkoxy‐4,7‐dimethoxybenzofuran‐5‐yl)ethylidene)‐2‐methyl‐2l4‐diazane‐1‐carbothioamides with hydrazonoyl halides. Also, 1‐(4,7‐dimethoxybenzofuran‐5‐yl)‐3‐phenylprop‐2‐en‐1‐one derivatives were used for synthesis of another series of 1,3‐thiazole‐pyrazole‐benzofuran. The structure of the newly synthesized products was elucidated via elemental analysis, spectral data, and alternative routes whenever possible. Seven new compounds were evaluated for their anticancer activity against the human breast carcinoma (MCF‐7) cell lines compared with doxorubicin drug. The results revealed that some new compounds showed promising anticancer activity.     

Norlignans and Phenylpropanoids from Metasequoia glyptostroboides Hu et Cheng

Five new compounds, i.e., the three new norlignans metasequirins G–I ( 1 – 3 ) and the two new phenylpropanoids 7‐(3‐ethoxy‐5‐methoxyphenyl)propane‐7,8,9‐triol (=1‐(3‐ethoxy‐5‐methoxyphenyl)propane‐1,2,3‐triol; 4 ) and 7‐(3‐hydroxy‐5‐methoxyphenyl)propane‐7,8,9‐triol (=1‐(3‐hydroxy‐5‐methoxy‐phenyl)propane‐1,2,3‐triol; 5 ), were isolated from the branches and stems of Metasequoia glyptostroboides Hu et Cheng . Their structures were elucidated by physical, chemical, and spectroscopic methods, including 1D‐ and 2D‐NMR and HR‐ESI‐MS. The cytotoxicites of the five compounds were tested against A549 and Colo 205 cell lines by the MTT method.     

Synthesis and Biological Study of Some 4-oxo-Thiazolidine Derivatives of 2-Aminothiazole

Conventional and microwave assisted synthesis of new series of N‐[2‐{2‐(substituted phenyl)‐4‐oxo‐5‐(substituted benzylidene)‐1,3‐thiazolidine}‐iminoethyl]‐2‐aminothiazole 5a–5m have been developed. The cycloaddition reaction of thioglycolic acid with N‐{2‐(substituted benzylidenehydrazino)‐ethyl}‐2‐aminothiazole 3a–3m in the presence of anhydrous ZnCl₂ afforded new heterocyclic compounds N‐[2‐{2‐(substituted phenyl)‐4‐oxo‐1,3‐thiazolidine}‐iminoethyl]‐2‐aminothiazole 4a–4m . The later product on treatment with several selected substituted aromatic aldehydes in the presence of C₂H₅ONa undergoes Knoevenagel reaction to yield 5a–5m . The structures of compounds 1 , 2 , 3a–3m , 4a–4m and 5a–5m were confirmed by IR, ¹H NMR, ¹³C NMR, FAB‐Mass and chemical analysis. All above compounds were screened for their antimicrobial activities against some selected bacteria and fungi and antituberculosis study against M. tuberculosis.     

Synthesis,structure and in vitro cytotoxicity testing of some 2‐aroylbenzofuran‐3‐ols

Five 2‐aroyl‐5‐bromobenzo[b]furan‐3‐ol compounds (two of which are new) and four new 2‐aroyl‐5‐iodobenzo[b]furan‐3‐ol compounds were synthesized starting from salicylic acid. The compounds were characterized by mass spectrometry and ¹H NMR and ¹³C NMR spectroscopy. Single‐crystal X‐ray diffraction studies of four compounds, namely, (5‐bromo‐3‐hydroxybenzofuran‐2‐yl)(4‐fluorophenyl)methanone, C₁₅H₈BrFO₃, (5‐bromo‐3‐hydroxybenzofuran‐2‐yl)(4‐chlorophenyl)methanone, C₁₅H₈BrClO₃, (5‐bromo‐3‐hydroxybenzofuran‐2‐yl)(4‐bromophenyl)methanone, C₁₅H₈Br₂O₃, and (4‐bromophenyl)(3‐hydroxy‐5‐iodobenzofuran‐2‐yl)methanone, C₁₅H₈BrIO₃, were also carried out. The compounds were tested for their in vitro cytotoxicity on the four human cancer cell lines KB, Hep‐G2, Lu‐1 and MCF7. Six compounds show good inhibiting abilities on Hep‐G2 cells, with IC₅₀ values of 1.39–8.03 µM.     

A New Cyclic Peptide and a New Steroid from the Fungus Penicillium sp. GD6 Isolated from the Mangrove Bruguiera gymnorrhiza

A rare new cyclic tetrapeptide, 5,5′‐epoxy‐MKN‐349A ( 1 ), featured by a MKN‐349A ( 5 ) skeleton and containing an uncommon ether bridge between C(5) and C(5′), and a new steroid, named 11‐O‐acetyl‐NGA0187 ( 2 ), together with two known steroids, 3 and 4 , were isolated from an endophytic fungus Penicillium sp. GD6 associated with the Chinese mangrove Bruguiera gymnorrhiza. The structures of the new compounds were elucidated on the basis of extensive spectroscopic analyses and by comparison with the data of related compounds reported in literature. Neither of the compounds 3 and 4 , isolated in this study, showed obvious bioactivities in the antibacterial bioassay experiments.     

Synthesis and Antimicrobial Screening of 2‐Aryl‐5‐((2‐arylthiazol‐4‐yl)methyl)‐1,3,4‐oxadiazole Derivatives

A new series of 2‐aryl‐5‐((2‐arylthiazol‐4‐yl)methyl)‐1,3,4‐oxadiazole derivatives was synthesized by condensation of 2‐(2‐substituted thiazol‐4‐yl)acetohydrazide with aryl aldehydes followed by oxidative cyclocondensation using iodobenzene diacetate. The structure of synthesized compounds was characterized by IR, NMR, and mass analysis. All the newly synthesized compounds were evaluated for their in vitro antimicrobial activity. Some of the compounds showed moderate antimicrobial activity.     

An Eco‐friendly Synthesis and Biological Screening of Fused Heterocyclic Compounds Containing a Thiophene Moiety via Gewald Reaction

5‐Amino‐3‐phenyl‐1‐(2,4,6‐trichlorophenyl)‐1H‐thieno[3,2‐c]pyrazole‐6‐carbonitrile ( 2 ) was designed and synthesized by one‐pot multicomponent reaction. Compound 2 was reacted with different reagents to obtain new condensed moieties with our thienopyrazole skeleton. The compounds were prepared by using environmentally benign techniques as microwave irradiation, ultrasonic irradiation, and ball‐milling. The structure of the prepared compounds was elucidated through spectroscopic methods. The new compounds were evaluated for their in vitro antibacterial and antifungal potentialities.     

Cytotoxic 5‐Hydroxyindole Alkaloids from the Marine Sponge Scalarispongia sp.

Three new 5‐hydroxyindole alkaloids ( 1 , 2 , 3 ) along with seven known analogs ( 4 , 5 , 6 , 7 , 8 , 9 , 10 ) were isolated from a Dokdo marine sponge Scalarispongia sp. The elucidation of the structures of the new compounds by spectroscopic analyses indicated that these compounds were an indole glyoxylate ( 1 ), a mono‐indole analog of hyrtinadine A ( 2 ), and a symmetrical bis‐indole with pyridine linker ( 3 ). The comparison of IC₅₀ values for obtained compounds against a human leukemia cell line revealed that the bis‐indole structure is a requirement for cytotoxicity.     

Synthesis and Antimicrobial Activity of New Pyrimidine Derivatives Incorporating 1H‐Tetrazol‐5‐ylthio Moiety

In this study, some new 4,6‐dimethoxy pyrimidine derivatives were synthesized. 2‐Amino‐4,6‐dimethoxy‐5‐thiocyanatopyrimidine ( 2 ) was synthesized by a reaction of 2‐amino‐4,6‐dimethoxypyrimidine with KSCN and was converted into 2‐amino‐5‐(1H‐tetrazol‐5‐ylthio)‐4,6‐dimethoxypyrimidine ( 4 ) by treatment with NaN₃ in the presence of NH₄Cl in DMF. Then, 1,5‐disubstitute tetrazole compounds were obtained from 4 by the alkylation reaction. In addition, some 2‐chloro‐4,6‐dimethoxy‐5‐substitute‐pyrimidines were synthesized by the diazotization method. The structures of these compounds were established on the basis of IR, ¹H NMR, APT, and HRMS spectral data and were evaluated for antibacterial activities against various bacterial strains. The results showed that some of these compounds exhibited good antibacterial activity as that of standard antibiotics Penicillin, Ampicillin, and Erythromycin.     

Chemical Constituents of the Endophytic Fungus Phomopsis sp. A240 Isolated from Taxus chinensis var. mairei

A new sesquiterpene, eremophil‐9‐ene‐11,12,13‐triol ( 1 ), a new oxazole, 4‐(2‐hydroxyethyl)‐5‐methyloxazole ( 2 ), and the two known lactones, 5′‐hydroxyalternariol ( 3 ) and alternariol ( 4 ), were isolated from the extract of Phomopsis sp. A240, an endophytic fungus isolated from the bark of Taxus chinensis var. mairei. The structures of the isolated compounds were determined by analyses of their spectroscopic data, as well as by comparison with literature reports. The isolated compounds were evaluated for their cytotoxic and antioxidant activities.     

Two New Sesquiterpenes from the Marine Fungus Eutypella scoparia FS26 from the South China Sea

A new monocyclofarnesane‐type sesquiterpene, 3,7,10‐trihydroxy‐6,11‐cyclofarnes‐1‐ene ( 1 ), and a new acorane‐type sesquiterpene, 8‐(hydroxymethyl)‐1‐(2‐hydroxy‐1‐methylethyl)‐4‐methylspiro[4.5]dec‐8‐en‐7‐ol ( 2 ), were isolated from the culture of Eutypella scoparia FS26 from the South China Sea, along with three known terpenes, 3 – 5 . The structures of these compounds were determined by extensive analysis of their spectroscopic data as well as by comparison with literature reports. The isolated compounds 1 – 5 were evaluated for their cytotoxic activities against the SF‐268, MCF‐7, and NCI‐H460 tumor cell lines.     

Ferrocenyl Ionic Compounds Containing [Fe(CN)6]3– Anions: Synthesis,Characterization, and Catalytic Effects during Combustion

Twenty‐eight novel ferrocenyl ionic compounds, composed of mononuclear 1‐ferrocenylmethylalkyldimethylammoniums, 1‐ferrocenylmethyl‐3‐alkylimidazoliums, or their dinuclear analogs and [Fe(CN)₆]^3– anion, were designed and synthesized to tackle significant volatility and migration tendency of ferrocene‐based burning rate catalysts (BRCs) used currently in the composite solid propellants. The new compounds were characterized by UV/Vis, FT‐IR, and elementary analysis. The crystal structures of compounds 2· 5H₂O and 3· CH₂Cl₂ · 4H₂O verified the successful preparation of the desired ionic compounds. The TG tests at 70 °C for 24 h revealed that the new compounds exhibit lower volatility than catocene. The cyclic‐voltammetry results suggested that new compounds are quasi‐reversible or irreversible redox systems. TheTG/DSC analyses exhibited that the compounds are of highly thermal stability. Their catalytic effects on the thermal degradation of ammonium perchlorate (AP), 1,3,5‐trinitro‐1,3,5‐triazacyclohexane (RDX), and 1,3,5,7‐tetranitro‐1,3,5,7‐tetrazacyclooctane (HMX) were investigated. The results showed that most of the compounds exert great effects on the thermal degradation of AP and RDX during combustion. 11 and 2 are comparable to catocene in the thermal decomposition of AP and RDX, respectively, and can therefore be used as alternatives of catocene in a composite solid propellant. Some new compounds are unexpectedly active in promoting the thermal disintegration of HMX.     

Synthesis and antibacterial activity of novel series of 2‐(p‐tolyloxy)‐3‐(5‐(pyridin‐4‐yl)‐1,3,4‐oxadiazol‐2‐yl)quinoline

A new series of 2‐(p‐tolyloxy)‐3‐(5‐(pyridin‐4‐yl)‐1,3,4‐oxadiazol‐2‐yl)quinoline were synthesized from oxidative cyclization of N′‐((2‐(p‐tolyloxy)quinoline‐3‐yl)methylene)isonicotinohydrazide in DMSO/I₂ at reflux condition for 3–4 h. The structures of the new compounds were confirmed by elemental analyses as well as IR, ¹H‐NMR, and mass spectral data. All the synthesized compounds were screened for their antibacterial activities against various bacterial strains. Several of these compounds showed potential antibacterial activity. J. Heterocyclic Chem., (2011).     

Strontium Nitriminotetrazolates – Suitable Colorants in Smokeless Pyrotechnic Compositions

The new compounds strontium 5‐nitriminotetrazolate dihydrate ( 1 ), strontium bis(1‐hydro‐5‐nitriminotetrazolate) tetrahydrate ( 2 ), strontium bis(1‐methyl‐5‐nitriminotetrazolate) monohydrate ( 3 ) and strontium bis(2‐methyl‐5‐nitraminotetrazolate)·x H₂O (x = 2–4) ( 4 ) were synthesized by the reactions of strontium hydroxide octahydrate and 5‐nitriminotetrazole ( 5 ), 1‐methyl‐5‐nitriminotetrazole ( 6 ) and 2‐methyl‐5‐nitraminotetrazole ( 7 ), respectively. The compounds were characterized using multinuclear NMR spectroscopy, vibrational (IR and Raman) spectroscopy, elemental analysis and differential scanning calorimetry. The solid state structures of 1 , 2 , 3 and 4 were determined using low temperature X‐ray diffraction. In addition, the sensitivities (impact, friction, electrical discharge) of 1 – 4 were investigated and their use as red colorants in pyrotechnic compositions was tested.