Cyclic Guanidines Research Articles

14N NMR Studies on Cyclic Nitramines. Correlations of Chemical Shifts with Nitrogen Partial Atomic Charge and .pi.-Orbital Overlap

The 14 N chemical shifts of nitro groups in the NMR spectra of cyclic nitramines have been correlated with their electronic environment in the minimium energy conformers determined using AM1 semiempirical molecular orbital calculations. Both the Mulliken population-derived atomic charge at the nitro nitrogen and the extent of π-orbital overlap influence the observed shifts. Equations useful for predicting the shifts of nitro groups bonded to either the imino group of cyclic guanidines or secondary amines and ureas in heterocycles have been derived and are discussed

ChemInform Abstract: Cyclic Guanidines. Part 5. Synthesis of Novel Benzodiazepinoid and Related Systems by Intramolecular Electrophilic Aromatic Substitution.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Cyclic Guanidines; V.1Synthesis of Novel Benzodiazepinoid and Related Systems by Intramolecular Electrophilic Aromatic Substitution

A convenient route to pentacyclic benzodiazepines and quinoxalines is reported, which simultaneously represent cyclic guanidines. Five new heterocyclic ring systems are described and the rules governing the regioselectivity of some of the ring closure reactions are studied. The structure of one of the products is confirmed by X-ray analysis. Scope and versatility of the process are indicated by several examples.

Synthesis of Cyclic Nitramines From Products of the Cyclocondensation Reaction of Guanidine With 2,3,5,6-Tetrahydroxypiperazine-1,4-dicarbaldehyde

The reaction of 2,3,5,6-tetrahydroxypiperazine-1,4-dicarbaldehyde (1) with guanidine hydrochloride in hydrochloric acid can be controlled to give 2,6-diiminododecahydrodiimidazo[4,5-b:4′,5′-e] pyrazine (2a) or the cis isomer of 4,5-diamino-2-iminoimidazolidine (4). Compound (4) reacts with formaldehyde, or formic acid followed by reduction, to give 2-iminooctahydroimidazo[4,5-d] imidazole (7). Treatment of (2a) or (7) with nitric acid gives dinitro derivatives that were isolated as nitric acid salts of the cyclic guanidines. Reaction of the dinitro derivatives with nitric acid/acetic anhydride in the presence of chloride ion gives 4,8-dinitro-2,6-bis( nitroimino ) dodecahydrodiimidazo -[4,5-b:4′,5′-e] pyrazine (3a) and 1,3-dinitro-5-( nitroimino ) octahydroimidazo [4,5-d] imidazole (9). The reaction of (7) with nitric acid/ trifluoroacetic anhydride was controlled to give either the tetranitro or a dinitro bis ( trifluoroacetyl ) derivative of the corresponding bicyclic urea.

ChemInform Abstract: Cyclic Guanidines. Part 1. Intramolecular Mercury(II)‐Induced Amination of Alkenes as a Convenient Route to Bicyclic Guanidines.

AbstractIntramolecular aminomercuration of the monocyclic alkenylguanidines (I), (IV), (VI), (IX), and (XII) followed by reduction with sodium borohydride yields bicyclic guanidines as shown in the reaction scheme.

Cyclic Guanidines; I. Intramolecular Mercury(II)-Induced Amination of Alkenes as a Convenient Route to Bicyclic Guanidines

Cyclic Guanidines; I. Intramolecular Mercury(II)-Induced Amination of Alkenes as a Convenient Route to Bicyclic Guanidines

ChemInform Abstract: Cyclic Guanidines. Part 15. Synthesis and Biological Activities of (Substituted Phenyl)‐imidazo[1,2‐a]imidazole Derivatives.

AbstractEntsprechenddem Formelschema werden nach zwei verschiedenen Methoden, ausgehend von den Aldehyden (I) oder den Epoxiden (VI), die im Titel genannten Heterocyclen (V), von denen einige blutdrucksenkende und diuretische Wirkung zeigen, synthetisiert.

Cyclic guanidines. XV. Synthesis and biological activities of (substituted phenyl)-imidazo[1,2-a]imidazole derivatives.

A series of (substituted phenyl)-2, 3, 5, 6-tetrahydro-1H-imidazo [1, 2-a] imidazoles (10) and their 2- or 3-oxo derivatives (20 and 21) were unambiguously prepared. These compounds were evaluated for antihypertensive and diuretic activities. Antihypertensive activity in spontaneously hypertensive rats (SHR) was observed in the series of compounds 10, whereas compounds 20 and 21 did not possess the activity. Diuretic effects in SHR and normotensive rats were observed in both the series of 10 and the 2- or 3-oxo derivatives (20 and 21). The relationship between the activities and the substituents on the phenyl ring is discussed.

Cyclic guanidines. XVI. Synthesis and biological activities of tetracyclic imidazo[2,1-b]quinazolinone derivatives.

Synthese et activite d'inhibiteur de thromboagregation de derives de cyclopenta et benzo [f ou g) imidazo [2,1-b] quinazolinones et d'imidazo [2,1-b] pyrido [2,3-f(3,2-f ou 3,4-f)] quinazolinones

ChemInform Abstract: SYNTHESIS OF CYCLIC GUANIDINES FUSED WITH AROMATIC RING THROUGH METAL ION PROMOTED CYCLIZATION

AbstractUnter milden Bedingungen werden die aus den Diaminen (I) und den Irnidothiocarbonat‐Derivaten (II) erhaltenen Isothioharnstoffderivate (III) in Gegenwart von Ag‐ und Hg‐Salzen zu den Guanidinen (IV) cyclisiert.

Synthesis of Cyclic Guanidines Fused with Aromatic Ring through Metal Ion Promoted Cyclization

Abstract A convenient synthetic method of five- and six- membered cyclic guanidines fused with aromatic ring was presented. 2-Aminoaniline or 2-(aminomethyl)aniline was treated with dimethyl carbonimidodithioates to give isothiourea which was cyclized to cyclic guanidine by using soft metal cations (Ag+, Hg2+).

ChemInform Abstract: PTILOCAULIN AND ISOPTILOCAULIN, ANTIMICROBIAL AND CYTOTOXIC CYCLIC GUANIDINES FROM THE CARIBBEAN SPONGE PTILOCAULIS AFF. P. SPICULIFER (LAMARCK, 1814)

Chemischer InformationsdienstVolume 12, Issue 50 Natural Products ChemInform Abstract: PTILOCAULIN AND ISOPTILOCAULIN, ANTIMICROBIAL AND CYTOTOXIC CYCLIC GUANIDINES FROM THE CARIBBEAN SPONGE PTILOCAULIS AFF. P. SPICULIFER (LAMARCK, 1814) G. C. HARBOUR, G. C. HARBOURSearch for more papers by this authorA. A. TYMIAK, A. A. TYMIAKSearch for more papers by this authorK. L. JUN. RINEHART, K. L. JUN. RINEHARTSearch for more papers by this authorP. D. SHAW, P. D. SHAWSearch for more papers by this authorR. G. JUN. HUGHES, R. G. JUN. HUGHESSearch for more papers by this authorS. A. MIZSAK, S. A. MIZSAKSearch for more papers by this authorJ. H. COATS, J. H. COATSSearch for more papers by this authorG. E. ZURENKO, G. E. ZURENKOSearch for more papers by this authorL. H. LI, L. H. LISearch for more papers by this authorS. L. KUENTZEL, S. L. KUENTZELSearch for more papers by this author G. C. HARBOUR, G. C. HARBOURSearch for more papers by this authorA. A. TYMIAK, A. A. TYMIAKSearch for more papers by this authorK. L. JUN. RINEHART, K. L. JUN. RINEHARTSearch for more papers by this authorP. D. SHAW, P. D. SHAWSearch for more papers by this authorR. G. JUN. HUGHES, R. G. JUN. HUGHESSearch for more papers by this authorS. A. MIZSAK, S. A. MIZSAKSearch for more papers by this authorJ. H. COATS, J. H. COATSSearch for more papers by this authorG. E. ZURENKO, G. E. ZURENKOSearch for more papers by this authorL. H. LI, L. H. LISearch for more papers by this authorS. L. KUENTZEL, S. L. KUENTZELSearch for more papers by this author First published: December 15, 1981 https://doi.org/10.1002/chin.198150342AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume12, Issue50December 15, 1981 RelatedInformation

Ptilocaulin and isoptilocaulin, antimicrobial and cytotoxic cyclic guanidines from the Caribbean sponge Ptilocaulis aff. P. spiculifer (Lamarck, 1814)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPtilocaulin and isoptilocaulin, antimicrobial and cytotoxic cyclic guanidines from the Caribbean sponge Ptilocaulis aff. P. spiculifer (Lamarck, 1814)Gary C. Harbour, Adrienne A. Tymiak, Kenneth L. Rinehart Jr., Paul D. Shaw, Robert Hughes Jr., Stephen A. Mizsak, John H. Coats, Gary E. Zurenko, Li H. Li, and Sandra L. KuentzelCite this: J. Am. Chem. Soc. 1981, 103, 18, 5604–5606Publication Date (Print):September 1, 1981Publication History Published online1 May 2002Published inissue 1 September 1981https://doi.org/10.1021/ja00408a071RIGHTS & PERMISSIONSArticle Views239Altmetric-Citations61LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (343 KB) Get e-Alerts Get e-Alerts

Cyclic guanidines. XI. Hydroxy and aminoimidazo[2,1-b]-quinazolines and related compounds.

Cyclic guanidines. XI. Hydroxy and aminoimidazo[2,1-b]-quinazolines and related compounds.

Cyclic guanidines. X. Synthesis of 2-(2,2-disubstituted ethenyl- and ethyl)-2-imidazolines as potent hypoglycemics.

2-(2, 2-Disubstituted ethenyl-and ethyl)-2-imidazoline derivatives (11, 14) were prepared by direct cyclization of active intermediates, 3, 3-disubstituted acrylimidic ethyl esters (9, 10), with ethylenediamine. The stereoisomers, (Z)-and (E)-3-phenyl-3-pyridylacrylic acid esters (6c-e), nitriles (7c-e) and amides (8c-e), as well as (Z)-and (E)-3-phenyl-3-pyridylacrylimidic acid esters (10c-e), and (Z)-and (E)-2-(2-pyridylethenyl)-2-imidazolines (11c-e), were isolated. Their structures are discussed. Compounds 11 and 14 showed potent hypoglycemic activity.

Cyclic guanidines. IX. Synthesis of 2-amino-3,4-dihydroquinazolines as blood platelet aggregation inhibitors.

A series of aryl-or aralky-substituted 2-amino-3, 4-dihydroquinazolines and related compounds were synthesized. The compounds were evaluated for inhibitory activity towards collagen-and ADP-induced aggregation of rat blood platelet in vitro and ex vivo. A group of 3-benzyl-substituted derivatives had potent activity. The structure-activity relationships are discussed.

Cyclic guanidines. XII. Synthesis and characterization of tricyclic guanidinium salts and related compounds.

The synthesis and characterization of tricyclic guanidinium salts and their reduced polycyclic trisaminomethane derivatives are described. N-ω-Chloroalkyl bicyclic guanidines (3) readily gave tricyclic guanidinium salt (4) in a neutral medium. Treatment of the compounds 4 with anion exchange resin caused facile ring cleavage to yield various macrocyclic compounds 6-9. The compounds 6-9 reverted to the parent tricyclic guanidinium salts in acidic and basic media as a result of transannular interactions. The guanidinium salts 4 were reduced with sodium borohydride to polycyclic trisaminomethane derivatives (11). The structures of 6-9 and 11 are proposed on the basis of the spectral data.

Cyclic guanidines XIII. Synthesis of 2-amino-4-phenyl-3,4-dihydrothieno(2,3-d)pyrimidine derivatives.

A method for the synthesis of 2-amino-4-phenyl-3, 4-dihydrothieno [2, 3-d] pyrimidine derivatives (12 and 13b) is described. Reduction of the 3-substituted 2, 3-dihydrothieno- [2, 3-d] pyrimidin-2-one (4c) and -2-thione (9b, c) with sodium borohydride gave the 1, 2, 3, 4-tetrahydro derivatives (6c and 10b, c), whereas the 3-unsubstituted compound 4a could be reduced only with lithium aluminum hydride to afford the 1, 2, 3, 4-tetrahydro derivative 6a. The 2-chloro derivative (7) was reduced with sodium borohydride to give the 2-chloro-3, 4-dihydro derivative 8a, which was reacted with ethyl bromoacetate to yield predominantly the 3-substituted derivative (8c). Amination of 8c gave compound 12. Methylation of 10b and 10c, followed by amination similarly yielded 13b and 12, respectively. In this amination some oxidative products (14) were also obtained. Compounds 12 and 13b had lower inhibitory effects against blood platelet aggregation than the quinazoline analogs (1) and (2).

Cyclic guanidines. II. Synthesis of hypoglycemic acyl or alkyl derivatives of 1-substituted 2-imino-1,3-diazacycloalkane.

Synthesis of acyl and alkyl derivatives of 1-benzyl or 1-benzhydryl-2-imino-1, 3-diazacycloalkanes (1) was attempted. Acetylation of 1a, c having five-membered ring with ethyl acetate gave 2-acetyl derivatives. However, reactions of 1a, c with dialkylcarbonate, acyl chloride and alkyl or aryl isocyanate afforded a mixture of 2- and 3-substituted compounds and reactions of 1a, c with isothiocyanate derivatives gave predominantly 3-substituted compounds. On the other hand, 1b, d having six-membered ring gave predominantly 2-substituted compounds by the similar reactions. Direct alkylation of 1a, c with alkyl iodide in the presence of sodium hydride yielded 3-alkyl derivatives (5). In the similar alkylations, 2-alkoxycarbonylimino and 2-cyanoimino derivatives, 2 and 9, gave 3-alkyl compounds 7 and 8, in which 2-alkaxycarbonyl and 2-cyano groups were removed on heating in t-butanol containing a small amount of hydrochloric acid to give 5 in good yields. Heating 7 and 8 having 1-benzhydryl group with sodium hydride gave 2-oxo- or 2-imino-3, 3-diphenylimidazo [1, 2-a] [1, 3] diazacycloalkane derivatives (10, 11 and 12). Some of 1-substituted 3-acyl and 3-alkyl-2-imino-1, 3-diazacycloalkanes showed hypoglycemic activity.

Syntheses of and structural assignments for some N-phosphono-2-iminoimidazolidines (cyclic guanidines)

Syntheses of and structural assignments for some N-phosphono-2-iminoimidazolidines (cyclic guanidines)