279 research outputs found
FIRST FORMATION OF THIEPINO[2,3-b]- AND THIEPINO[3,2-a]-INDOLIZINE DERIVATIVES
The reactions of potassium 1,3-bis(ethoxycarbonyl)indolizine-2-thiolates with ethyl 4-bromocrotonate afforded the corresponding indolizine derivatives having (E)-(3-ethoxycarbonyl-2-propenyl)thio, (E)- and (Z)-(3-ethoxycarbonyl-1-propenyl)thio group at the 2-position. The alkaline treatment of these S-alkylated indolizines gave the title compounds in good yields.ArticleHETEROCYCLES. 78(2): 319-324 (2009)journal articl
PREPARATION OF NEW NITROGEN-BRIDGED HETEROCYCLES. 63. UNEXPECTED FORMATION OF THIENO[3 ',4 ':4,5]IMIDAZO[1,2-a]-PYRIDINES
The alkaline treatment and dehydrogenation of pyridinium salts, obtainable from the S-alkylation of 3,5-dimethylpyridinium 2-alkylthio-1-cyano2-thioxoethylides with some phenacyl bromides, afforded unexpected heterocycles, 3-alkylthio-1-arylcarbonyl-6,8-dimethylthieno[3',4':4,5]imidazo-[1,2-a]pyridines, together with the corresponding 2-alkylthio-1-arylcarbonylthio-6,8-dimethylindolizine-3-carbonitriles.ArticleHETEROCYCLES. 76(1): 391-399 (2008)journal articl
Base-induced generation of aryl(1,2,3-triazol-1-yl)carbenes from 1-[(N-phenylsulfonyl)benzohydrazonoyl]-1,2,3-triazoles and their ring enlargement to 3-aryl-1,2,4-triazines
The Bamford-Stevens reactions of 1-[N-(phenylsulfonyl)benzohydrazonoyl]-1,2,3-triazole derivatives, readily available from the 1,3-dipolar cycloadditions of N-(phenylsulfonyl)benzohydrazonoyl azides with enamines, were examined and the transformation from aryl(1,2,3-triazol-1 -yl)carbene intermediates to the corresponding 3-aryl-1,2,4-triazine derivatives was first observed.ArticleHETEROCYCLES. 65(2): 279-286 (2005).journal articl
Asymmetric cycloaddition reactions between 2-benzopyrylium-4-olates and 3-(2-alkenoyl)-2-oxazolidinones in the presence of 2,6-bis(oxazolinyl)pyridine-lanthanoid complexes
ArticleTetrahedron. 62(39): 9218-9225 (2006)journal articl
Syntheses of some 1-(alpha-hydroxybenzyl)thieno[3,4-b]indolizine derivatives and their unexpected condensation reactions
Some ethyl 3-(benzyl or methylthio)-1-(alpha-hydroxybenzyl)- thieno[3,4-b]indolizine-9-carboxylates were prepared by the reduction of the corresponding 1-benzoyl derivatives with sodium borohydride. These compounds were considerably unstable and their treatment with acetic acid afforded the unexpected condensation products.ArticleHETEROCYCLES. 65(7): 1557-1560 (2005)journal articl
First ring contraction-desulfurization of 1-(arylcarbonyl)pyrido[2,1-c]-1,4-thiazines to 1-(arylcarbonyl)indolizines and its application to 3-arylthieno[3,2-a]indolizine synthesis
The ring contraction-desulfurization route from transient 1-(arylcarbonyl)pyridol2,1-c]-1,4-thiazine intermediates, generated in situ from the treatment of the corresponding pyridinium salts with a base and then a dehydrogenation agent, to 1-(arylcarbonyl)indolizines was first observed. By using this route three 1-arylcarbonyl-6,8-dimethylindolizines having the protected 2-thiol group were prepared and their transformation to 2-acyl-3-arylthieno[3,2-a]indolizine derivatives were performed in good yields.ArticleHETEROCYCLES. 74: 521-532 (2007)journal articl
Different photochemical behavior of bis(biphenyl)ethylenes and ethenes in solution and in the solid-state: Structurally controlled Z/E-photoisomerization in the solid-state
ArticleJOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY. 184(1-2): 44-49 (2006)journal articl
Expert consensus document: Semantics in active surveillance for men with localized prostate cancer — results of a modified Delphi consensus procedure
Active surveillance (AS) is broadly described as a management option for men with low-risk prostate cancer, but semantic heterogeneity exists in both the literature and in guidelines. To address this issue, a panel of leading prostate cancer specialists in the field of AS participated in a consensus-forming project using a modified Delphi method to reach international consensus on definitions of terms related to this management option. An iterative three-round sequence of online questionnaires designed to address 61 individual items was completed by each panel member. Consensus was considered to be reached if ≥70% of the experts agreed on a definition. To facilitate a common understanding among all experts involved and resolve potential ambiguities, a face-to-face consensus meeting was held between Delphi survey rounds two and three. Convenience sampling was used to construct the panel of experts. In total, 12 experts from Australia, France, Finland, Italy, the Netherlands, Japan, the UK, Canada and the USA participated. By the end of the Delphi process, formal consensus was achieved for 100% (n = 61) of the terms and a glossary was then developed. Agreement between international experts has been reached on relevant terms and subsequent definitions regarding AS for patients with localized prostate cancer. This standard terminology could support multidisciplinary communication, reduce the extent of variations in clinical practice and optimize clinical decision making
- …