Post-graduate theses

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Identifier	000034158
Title	Ολική σύνθεση πολυαμινικών αναλόγων και συζευγμάτων με βιολογικό ενδιαφέρον
Author	Βάσσης, Ευστράτιος
Thesis advisor	Παπαϊωάννου, Διονύσιος
Abstract	he aim of this dissertation was the development of a general methodology which would allow for the total synthesis of (a) N1- and N4- alkylated (e.g. ethylated) SPD analogs, (b) the SPD analogs of Kukoamine A SkukB and SkukC and (c) the alkaloid Tenuilobine. Key-intermediated for these synthesis were the isolable active esters Trt-βAla-OSu, Trt-βAla-γAba-OSu and Trt-γAba-βAla-OSu, where Trt is the triphelymethyl (trityl) group. The ester Trt-βAla-γAba-OSu was obtained through the condensation of Trt-βAla-OSu with the TMS ester of γAba, followed by the activation of the thus obtained dipeptide acid with HOSu and DCC. The ester Trt-γAba-βAla-OSu was obtained through the condensation of the Trt-γAba-OH with the methylester H-βAla-OMe, in the presence of HOBt and DCC, followed by saponification and activation of the thus obtained dipeptide acid with HOSu and DCC. Condensation of Trt-βAla-γAba-OSu with dibenzylamine, followed by reduction with LiAlH4, provided the N1-Trt-N8, N8-Bn2-SPD.The latter, with acetylation, followed by reduction with LiAlH4 and complete deprotection with catalytic hydrogenolysis, provived the N4-Et-SPD. On the other hand, acylation with HO2C(CH2)14CO2CH2COPh in the presence of the coupling agent PyBrOP and DIPEA, followed by phenacyl groyp removal with PhSNa, provided a new acid. This acid on condensation with N1, N4, N12- Trt3 -SPM, followed by detritylation and catalytic hydrogenolysis gave the alkaloid Tenuilobine. The required tritylated SPM was obtained through the double acylation of 1,4-diaminobutane with Trt-βAla-OSu, folowed by reduction with LiAlH4 and finally monotritylation with Trt-Cl and Et3N. Furthermore, N1-alkylated SPD such as N1-Et-SPD, were easily obtained from the active ester Trt-γAba-β-AlaOSu with aminolysis, followed by reduction with LiAlH4 and detritylation. Finally, the SPD Kukoamines SkukB and SkukC were prepared by using as starting materials the active esters Trt-γAba-βAla-OSu and Trt-βAla-γAba-OSu too, which through ammonoloysis, followed by reduction with LiAlH4, provided the N8-Trt-SPD and N1-Trt-SPD derivatives, respectively.
Language	Greek
Issue date	2001-03-01
Collection	School/Department--School of Sciences and Engineering--Department of Chemistry--Post-graduate theses
	Type of Work--Post-graduate theses
Permanent Link	https://elocus.lib.uoc.gr//dlib/d/c/0/metadata-dlib-2001vassis.tkl
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