AbstractThe N‐protected methoxycephem derivatives (IX) and (XII) are prepared as outlined in the reaction scheme.
ChemInformVolume 19, Issue 26 Natural Products ChemInform Abstract: Total Synthesis of Two 4-Ethoxycarbonyl Cephems (VI) with or without Phthalimido Functionalization at Position 7. A. RELIQUET, A. RELIQUET Lab. Chim. Org., CNRS, 44072 Nantes, Fr.Search for more papers by this authorJ. C. MESLIN, J. C. MESLIN Lab. Chim. Org., CNRS, 44072 Nantes, Fr.Search for more papers by this authorF. RELIQUET, F. RELIQUET Lab. Chim. Org., CNRS, 44072 Nantes, Fr.Search for more papers by this authorH. QUINIOU, H. QUINIOU Lab. Chim. Org., CNRS, 44072 Nantes, Fr.Search for more papers by this author A. RELIQUET, A. RELIQUET Lab. Chim. Org., CNRS, 44072 Nantes, Fr.Search for more papers by this authorJ. C. MESLIN, J. C. MESLIN Lab. Chim. Org., CNRS, 44072 Nantes, Fr.Search for more papers by this authorF. RELIQUET, F. RELIQUET Lab. Chim. Org., CNRS, 44072 Nantes, Fr.Search for more papers by this authorH. QUINIOU, H. QUINIOU Lab. Chim. Org., CNRS, 44072 Nantes, Fr.Search for more papers by this author First published: June 28, 1988 https://doi.org/10.1002/chin.198826328AboutPDF 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. Volume19, Issue26June 28, 1988 RelatedInformation
Diastereoisomeric couples of α-methoxy α-dihydrothiazinyl glycinates 1 were obtained by two different ways, with a proof of structure by X-Ray. 3,6-Dihydro-2H-1, 3-thiazine rings were obtained via (3+3) and (4+2) cyclocondensations, followed by regioselective reduction. These dihydrothiazine derivatives are potential precursors of cephamycins.
AbstractThe methylenedihydrothiazines (III) are prepared by cyclocondensation of the acrylates (II) with the thioacylformamidines (I).
La synthèse totale de deux éthoxycarbonyl-4 céphèmes est décrite. Pour l'un d'entre eux, l'introduction d'un groupement aminé en position 7, masqué par un phtalimido, rapproche encore la structure obtenue de celle des céphalosporines biologiquement actives.
AbstractThe thiazines (I) are brominated by NBS to form the derivatives (II) and (III).
5-Alkoxycarbonyl-6H-1,3-thiazines, precursors of cephems, are prepared by alkylation of 2-methylene-3, 6-dihydro-2H-1,3-thiazines or by conversion of the carbaldehyde substituted at the 5 position of a 6H-1,3-thiazine. These compounds give access to dihydrothiazinic acids converted into cephems in the presence of methanesulfonyl chloride in anhydrous chloroform. Les alkoxycarbonyl-5 6H-thiazines-1,3 précurseurs de céphèmes sont obtenues par alkylation de méthylène-2 2H-dihydro-3,6 thiazines-1,3 ou par conversion de la fonction carbaldéhyde d'une formyl-5 thiazine. Ces composés conduisent en deux étapes aux acides dihydrothiaziniques qui sont transformés en céphèmes par le chlorure de méthanesulfonyle en milieu anhydre.
The synthesis of new thiazines is described. Their structural determination and their spectroscopic parameters are examined. The [2 + 2] cyclocondensation of these thiazines with ketenes is studied along with the reversibility of the reaction as a function of the nature of the substituents on position 4 and (or) 5 of 6H-1,3-thiazines.
AbstractAus den Cyanessigsäureestern (I) werden über (II) die Thioamide (III) hergestellt, die mit den Amidaoetalen (IV) zu (V) und weiter mit den aktivierten v Olefinen (VI) zu den Dihydrothiazinen (VIII) reagieren.
Treatment with NBS of 2-methylene-3,6-dihydro-2H-1,3-thiazines carrying an ester function on 5 and a methyl on 4 gives the corresponding 4-bromomethyl and 4,4-dibromomethyl derivatives in a perfectly selective manner. The monobromo compounds give access to 4-aminomethyl, 4-alkoxymethyl, 4-alkylthiomethyl, 4-acetoxymethyl and 4-formyl thiazines. These aldehydes, also prepared from the dibromo derivatives, are converted into 4-cyano and 4-alkoxycarbonyl thiazines. In certain cases, interactions with the neighbouring ester group, leading to lactones are observed.
N-Protected7-amino-7-methoxy cephems are synthesised from methylN-(O-methoxycarbonylbenzoyl)methoxy(thiocarbamoyl)glycinate in two major steps: construction of the thiazine ring and subsequent closure of the β-lactam ring.
AbstractDie Titelverbindungen (II) lassen sich auf einfache Weise und in guter Ausb. aus den Estern (I) darstellen.
AbstractDas gemäß Formelschema aus dem Thioamid (I) zugängliche Dihydrothiazin (V) cyclisiert zu den enantiomeren Cephemen (VI) und (VII).
AbstractDas Thiazin (I) reagiert mit Wasser bzw. Schwefelwasserstoff (II) zu den Substitutionsprodukten (III).
Chemischer InformationsdienstVolume 14, Issue 43 Natural Products ChemInform Abstract: HETEROATOMIC ARRANGEMENTS AND CYCLIZATION PRODUCTS. VI. NEW SYNTHESIS OF CEPHEMS: 3-ACETYL-7-METHYL-7-PHTHALIMIDO-8-OXO-5-THIA-1-AZABICYCLO(4.2.0)OCT-2-ENE DIASTEREOMERS J.-C. ROZE, J.-C. ROZESearch for more papers by this authorJ.-P. PRADERE, J.-P. PRADERESearch for more papers by this authorG. DUGUAY, G. DUGUAYSearch for more papers by this authorA. GUEVEL, A. GUEVELSearch for more papers by this authorH. QUINIOU, H. QUINIOUSearch for more papers by this authorS. POIGNANT, S. POIGNANTSearch for more papers by this author J.-C. ROZE, J.-C. ROZESearch for more papers by this authorJ.-P. PRADERE, J.-P. PRADERESearch for more papers by this authorG. DUGUAY, G. DUGUAYSearch for more papers by this authorA. GUEVEL, A. GUEVELSearch for more papers by this authorH. QUINIOU, H. QUINIOUSearch for more papers by this authorS. POIGNANT, S. POIGNANTSearch for more papers by this author First published: October 25, 1983 https://doi.org/10.1002/chin.198343343Read the full textAboutPDF 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. Volume14, Issue43October 25, 1983 RelatedInformation
M. A. Riahi, M. Lees, M. Chehna, G. Duguay and H. Quiniou, J. Chem. Soc., Chem. Commun., 1983, 393 DOI: 10.1039/C39830000393
The total synthesis of two diastereomeric cephems is described with three original steps in excellent yields: construction of the 1,3-thiazine ring via a (4+2) cycloaddition reaction, regioselective hydrogenation of the carbon–nitrogen double bond, and lactamization using BOP.