المؤلفون: Yu. V. Revinskii, I. E. Tolpygin, V. A. Chernoivanov, Vladimir I. Minkin, Vladimir A. Bren

المصدر: Chemistry of Heterocyclic Compounds. 48:1503-1507

مصطلحات موضوعية: chemistry.chemical_compound, Photochromism, Diene, chemistry, Photoswitch, Bicyclic molecule, Organic Chemistry, Organic chemistry, Imidazolidines, Heterocyclic derivatives, Fluorescence

الوصف: 2-Substituted imidazolidines and hexahydropyrimidines have been obtained by the interaction of ethane-1,2-diamine and propane-1,3-diamine derivatives with 3-phenylbicyclo[2.2.1]hepta-2,5-diene-2-carbaldehyde. Investigation of their luminescent, photochromic, and sensor properties has shown the possibility of using these compounds as photoswitch pH sensors.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::6d30d2c6c2d616fdc6c29c3a18667cabTest
https://doi.org/10.1007/s10593-013-1164-xTest

المؤلفون: Srikanth Yellamelli Valli Venkata, Naseer Ahmed Khan Mohammed, Kashi Reddy Methuku, Kamal Ahmed, Farheen Sultana

المصدر: Expert Opinion on Investigational Drugs. 21:619-635

مصطلحات موضوعية: Pharmacology, Molecular Structure, Bicyclic molecule, Antineoplastic Agents, General Medicine, chemistry.chemical_compound, Benzothiazole, chemistry, Biological profile, Neoplasms, Biological property, Animals, Humans, Moiety, Organic chemistry, Pharmacology (medical), Benzothiazoles, Pharmacophore, Heterocyclic derivatives, Conjugate

الوصف: Benzothiazole scaffold comprises a bicyclic ring system and is known to exhibit a wide range of biological properties including antimicrobial and anticancer activities. Benzothiazole derivatives have long been therapeutically used for the treatment of various diseases. However, in recent years, 2-arylbenzothiazoles have emerged as an important pharmacophore in the development of antitumor agents. The promising biological profile and synthetic accessibility have been attractive in the design and development of new benzothiazoles and their conjugate systems as potential chemotherapeutics.This review mainly focuses on the structural modifications of benzothiazole scaffold, development of various series of benzothiazoles and their conjugates as new antitumor agents. Furthermore, heterocyclic derivatives bearing benzothiazole moiety and their in vitro as well as in vivo screening, structure-activity relationships (SAR), mechanism, pharmacokinetics, clinical use and their future therapeutic applications are discussed here.A large number of benzothiazole derivatives discussed here possess potent anticancer activity and can be further developed as drug candidates. Benzothiazole conjugates could also display synergistic effect and still there is a need to use the drug combinations permitting lower dose and development of new generation of drugs. Despite encouraging results that have been observed for their response to tumor in clinical studies, full characterization of their toxicity is further required for their clinical usage as safe drugs for the treatment of cancer. We believe that this review gives a better understanding and scope for future drug design and development of benzothiazole-based compounds to implicate their use in cancer chemotherapy.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::4353d34da8973488fceb1adfa5c49713Test
https://doi.org/10.1517/13543784.2012.676043Test

المؤلفون: Wael A. El-Sayed, Hala E. M. Tolan, Mohamed I. Hegab, Adel A.-H. Abdel-Rahman

المصدر: Monatshefte für Chemie - Chemical Monthly. 139:1055-1060

مصطلحات موضوعية: chemistry.chemical_compound, chemistry, Bicyclic molecule, Stereochemistry, Proton NMR, Oxadiazole, 1,2,4-Triazole, Thio, General Chemistry, Heterocyclic derivatives

الوصف: A series of new N- and S-substituted 1,3,4-oxadiazole derivatives were synthesized. 5-Pyridin-3-yl-3-[2-(5-thioxo-4,5-dihydro-l,3,4-thiadiazol-2-yl)ethyl]-1,3,4-oxadiazole-2(3H)-thione and 5-[(5-(pyridin-3-yl)-1,3,4-oxadiazol-2-ylthio)methyl]-N-phenyl-1,3,4-thiadiazol-2-amine were formed by cyclization of 3-(5-pyridin-3-yl-2-thioxo-1,3,4-oxadiazol-3(2H)-ylpropanimidohydrazide and 2-[(5-pyridin-3-yl-1,3,4-oxadiazol-2-yl)thio]thiosemicarbazide with CS2 and H2SO4. On the other hand, a number of new bicyclic 1,2,4-triazolo[3,4-b][1,3,4]thiadiazole derivatives were synthesized. 6-Pyridin-3-ylbis[1,2,4]‐triazolo[3,4-b:4′,3′-d][1,3,4]thiadiazole-3(2H)-thione was synthesized by reaction of 6-(hydrazino)-3-pyridine-3-yl[1,2,4]triazolo[3,4-b][1,3,4]thiadiazole with CS2/KOH/EtOH. The structures of the newly synthesized compounds were elucidated by the spectral and analytical data IR, Mass, and 1H NMR spectra.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::658717655a87b40968468ec169251b43Test
https://doi.org/10.1007/s00706-008-0881-9Test

المؤلفون: E. K. Mikitenko, Yu. L. Briks, N. N. Romanov

المصدر: Dyes and Pigments. 33:299-318

مصطلحات موضوعية: End-group, Bicyclic molecule, Chemistry, Process Chemistry and Technology, General Chemical Engineering, Spectral properties, Infrared spectroscopy, chemistry.chemical_element, Absorption (electromagnetic radiation), Photochemistry, Chemical synthesis, Heterocyclic derivatives, Nitrogen

الوصف: The development of methods of synthesizing new heterocyclic derivatives suitable for obtaining polymethine dyes is described. Compounds of this series are shown to have potential for the synthesis of deeply colored dyes, and which although having a short polymethine chain, absorb in the IR region. It is shown that structural modifications within the dyes enables the position of their absorption bands to be controlled over wide regions.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::5e993917161f65d2d0f292c992f01bafTest
https://doi.org/10.1016/s0143-7208Test(96)00046-0

المؤلفون: Martin Avalos, Pedro Cintas, Juan C. Palacios, Reyes Babiano, José L. Jiménez, Concepción Valencia

المصدر: Tetrahedron. 49:2655-2675

مصطلحات موضوعية: chemistry.chemical_compound, Classical literature, Bicyclic molecule, chemistry, Aryl, Organic Chemistry, Drug Discovery, Organic chemistry, Ring (chemistry), Biochemistry, Heterocyclic derivatives, Combinatorial chemistry

الوصف: The reactions of 2-amino-2-deoxyglycopyranoses with aryl isocyanates have been investigated in detail and ureas and heterocyclic derivatives are obtained. The mechanism of formation of glycofurano[2,1- d ]imidazolidin-2-ones 62 has now become visible, while previous reports and the classical literature dealing with the subject in question proposed alternative structures for the reaction products. The reactions are pH-dependent and only furanoid bicycles are smoothly obtained at acidic pH values, whereas in neutral or basic media 5-hydroxyimidazolidin-2-one derivatives 66 can be isolated. These monocyclic structures appear to be the true intermediates of the reaction and, under appropriate conditions, can be converted exclusively into the corresponding cis -fused five-membered ring systems. Likewise, the first cis -fused glycopyrano[2,1- d ]imidazolidin-2-ones 75 have been also prepared.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::804e39c97f9596e24b3a8ed2a81dda35Test
https://doi.org/10.1016/s0040-4020Test(01)86344-4

المؤلفون: Ali A. Abdel Hafez, Ragaa A. Ahmed, Ahmed A. Geies, Hussein El-Kashef

المصدر: Collection of Czechoslovak Chemical Communications. 58:1931-1936

مصطلحات موضوعية: chemistry.chemical_compound, chemistry, Bicyclic molecule, Hydrazine, Pyridine, Lactam, General Chemistry, Hydrate, Medicinal chemistry, Heterocyclic derivatives

الوصف: Ethyl 3-cyano-4,6-diphenyl-2-pyridylthioacetate (II) yielded with hydrazine hydrate hydrazides III, IV that both proved to be versatile compounds for the synthesis of new heterocyclic derivatives. Thus the thieno[2,3-bpyridine derivatives Xa - Xd and XIIa - XIId were obtained.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::5b620fa19f47781c92b85b9ec3784c95Test
https://doi.org/10.1135/cccc19931931Test

المؤلفون: José L. Jiménez, Pedro Cintas, Martin Avalos, Concepción Valencia, Juan C. Palacios, Reyes Babiano

المصدر: ChemInform. 25

مصطلحات موضوعية: chemistry.chemical_classification, Nucleophilic addition, Bicyclic molecule, chemistry, Nucleophile, Stereochemistry, Intramolecular force, Condensation, Glycoside hydrolase, General Medicine, Heterocyclic derivatives, Aldehyde

الوصف: The reactions of 2-amino- and 2-alkylamino-2-deoxyglycopyranoses with isothiocyanates gave thioureas and heterocyclic derivatives. Moreover, cis-fused glycopyrano[2,1-d]imidazolidin-2-thiones, which have a close structural analogy with some naturally-occurring glycosidase inhibitors, were synthesised for the first time. The mechanism of formation of glycofurano and glycopyrano[2,1-d]imidazolidin-2-thiones occurs via the intermediacy of monocyclic 5-hydroxyimidazolidin-2-thiones. These substances are generated by intramolecular nucleophilic addition of an NH group to the aldehyde function of the sugar. The monocyclic intermediates have been isolated and their participation in the formation of bicyclic imidazolidin-2-thiones and/or monocyclic imidazolin-2-thiones proved. In stark contrast, cis-fused glycopyranothiazolidines were prepared by nucleophilic displacements.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::729e8adec5b847c625cc543a0c08c927Test
https://doi.org/10.1002/chin.199429270Test

المؤلفون: Carlos Silva López, Olalla Nieto Faza, Angel R. de Lera

المصدر: The Journal of organic chemistry. 74(6)

مصطلحات موضوعية: Reaction mechanism, Electrocyclic reaction, Bicyclic molecule, Stereochemistry, Chemistry, Torquoselectivity, Organic Chemistry, Conrotatory and disrotatory, Ring (chemistry), Heterocyclic derivatives, Isomerization

الوصف: The ring opening reactions of fused cyclobutenes have been the subject of mechanistic debate for decades. Some reports have been published recently suggesting that, in some heterocyclic derivatives, the disrotatory anti-Woodward-Hoffmann mechanism might be responsible for the ring opening. We hereby show that the conrotatory pathway is still the lowest energy alternative for all cases examined, including push-pull substituted 2-thia-4-azabicyclo[3.2.0]hepta-3,6-dienes. Actually, we found that the disrotatory transition state exchanges roles with a double-bond isomerization depending on the substituents around the bicyclic structure.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::37e1428a1558f9bb194437a849f69be2Test
https://pubmed.ncbi.nlm.nih.gov/19219978Test

المؤلفون: Mohamed I. Hegab, Hala E. M. Tolan, Adel A.-H. Abdel-Rahman, Wael A. El-Sayed

المصدر: ChemInform. 39

مصطلحات موضوعية: chemistry.chemical_compound, Bicyclic molecule, Chemistry, Proton NMR, Triazole derivatives, Thio, Oxadiazole, 1,2,4-Triazole, General Medicine, Medicinal chemistry, Heterocyclic derivatives

الوصف: A series of new N- and S-substituted 1,3,4-oxadiazole derivatives were synthesized. 5-Pyridin-3-yl-3-[2-(5-thioxo-4,5-dihydro-l,3,4-thiadiazol-2-yl)ethyl]-1,3,4-oxadiazole-2(3H)-thione and 5-[(5-(pyridin-3-yl)-1,3,4-oxadiazol-2-ylthio)methyl]-N-phenyl-1,3,4-thiadiazol-2-amine were formed by cyclization of 3-(5-pyridin-3-yl-2-thioxo-1,3,4-oxadiazol-3(2H)-ylpropanimidohydrazide and 2-[(5-pyridin-3-yl-1,3,4-oxadiazol-2-yl)thio]thiosemicarbazide with CS2 and H2SO4. On the other hand, a number of new bicyclic 1,2,4-triazolo[3,4-b][1,3,4]thiadiazole derivatives were synthesized. 6-Pyridin-3-ylbis[1,2,4]‐triazolo[3,4-b:4′,3′-d][1,3,4]thiadiazole-3(2H)-thione was synthesized by reaction of 6-(hydrazino)-3-pyridine-3-yl[1,2,4]triazolo[3,4-b][1,3,4]thiadiazole with CS2/KOH/EtOH. The structures of the newly synthesized compounds were elucidated by the spectral and analytical data IR, Mass, and 1H NMR spectra.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::b347516f3210e83a17051ea4bc375d1fTest
https://doi.org/10.1002/chin.200849133Test

المؤلفون: M. A. Khalil, Nargues S. Habib

المصدر: Archiv der Pharmazie. 323:401-404

مصطلحات موضوعية: chemistry.chemical_classification, Bicyclic molecule, Stereochemistry, medicine.drug_class, Anticholesteremic Agents, Pharmaceutical Science, Carboxamide, Thioester, Sitosterols, Mice, chemistry.chemical_compound, chemistry, Drug Discovery, medicine, Animals, Phenols, Heterocyclic derivatives, Hypolipidemic Agents

الوصف: Four novel series of heterocyclic derivatives of β-sitosterol were prepared by the reaction of 3-β-sitosterol hemisuccinate with SOCl2 then with thiols, amines or phenols. These series are: 3β-[(3-substituted-4(3H)-quinazolinon-2-yl)thiocarbonylproprionyloxy]stigmast-5-ene; 3β([4-substituted-5-(4-pyridyl)-4H-1,2,4-triazol-3-yl]thiocarbonylpropionyloxy}stigmast-5-ene; 3β-[(5-substituted-1,3,4-thiadiazol-2-yl)carbamoylpropionyloxy]stigmast-5-ene and 3β-substituted carbanoyl or oxycarbonylpropionyloxy)stigmast-5-ene. The antilipidemic activity of representative compounds was studied. Antilipidaemische Verbindungen, 3. Mitt.: Synthese einiger heterocyclischer Derivate des β-Sitosterols Vier neue Serien heterocyclischer Derivate des β-Sitosterols wurden hergestellt durch Reaktion von β-Sitosterol-hemisuccinat mit SOCl2, gefolgt von Thiolen, Aminen oder Phenolen. Es handelt sich um 3β-3β-[(3-substituierte-4(3H)-Chinazolinon-2-yl)thiocarbonylproprionyloxy]stigmast-5-en; 3β-([4-substituierte-5-(4-Pyridyl)-4H-1,2,4-triazol-3-yl]thiocarbonylpropionyloxy} stigmast-5-en; 3β-[(5-substituierte-1,3,4-Thiadiazol-2-yl]carbamoylpropionyloxy]stigmast-5-en und 3β-(substituierte carbamoyl oder oxycarbanylpropionyloxy)stigmast-5-ene. Die antilipidaemische Aktivitat reprasentativer Verbindungen wurde gepruft.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::9dc708418af1834fa487f97c9f774b4eTest
https://doi.org/10.1002/ardp.19903230705Test