StatusThe thesis was presented on the 21 September, 2017
Approved by NCAA on the 11 May, 2018
Abstract– 0.93 Mb / in romanian
– 0.84 Mb / in english
5.17 Mb /
Thesis structure: introduction, 5 chapters, the first representing literature review and the next 4 chapters integrating the results of own investigations on the thesis subject, followed by general conclusions and recommendations, bibliography – 266 references, 219 pages of the main text, 121 Figures and 7 tables / Number of publications: research results have been published in 42 scientific works.
The aim and objectives of the thesis: Due to the fact that the majority of terpenic compounds which represent practical interest have complex carbon backbones and advanced functionalization with heteroatoms, the main aim of the current work was elaboration of synthesis methods for diverse classes of terpenic compounds by a flexible combination of major biomimetic processes, including oligomerization, cyclization, rearrangement and selective functionalization. The specific objectives of the work included the synthesis of terpenic compounds of different oligomeric series, having diverse functionalization pattern and their investigation in cyclization, rearrangement and heteroatom functionalization reactions.
Scientific novelty and originality of the research: A major influence of the functionalization pattern in the terpenoid skeletons on the cyclization/rearrangement reactions in vitro has been demonstrated in the present work. Addition of post-cyclization functionalization reactions to these synthetic transformations enlarge even more the arsenal of available synthetic tools for the generation of the entire structural diversity of terpenoids, preparing the ground for advanced studies on terpenic compounds utility in general. Conceptually novel scientific results for basic and applied science achieved: The current thesis has demonstrated the viability of the successive combination of different biomimetic processes for the synthesis of terpenic compounds with diverse structures. The relevant complexity of biogenetic paths which lead to the enormous structural diversity of terpenoids has prompted us to launch the hypothesis of the flexible combination of biosynthetic steps within biomimetic synthesis strategies. This approach has been defined as Random Biomimetic Synthesis. As a result of verification and valorization of thesis hypothesis, the synthesis of representatives from 15 different classes of terpenic compounds has been realized.
Theoretical and application value of the research: The main theoretical relevance of the work is based on the coining the Random Biomimetic Synthesis principle in planning the synthesis of complex natural product. The deep study of natural products with some specific structural features, basing on the same biogenetical root, has led to the identification of a super-family of cyclic terpenoids with terminal pendant prenyl groups. Implementation of the above mentioned scientific results has been expressed in the synthesis of 7 natural products or close precursors. In addition, initiation of research on ozonolytic cleavage of terpenoids in aqueous solvents has led to patenting of an efficient method for the production of sclareoloxide – an important compound with a broad use as component of aromatization compositions.