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81.
Venkata Naresh Vema Y. Bharathi kumari Sridhar Musulla RamaKrishnam Raju Addada Srinivasa Rao Alapati 《Tetrahedron letters》2018,59(47):4165-4167
Greensporone C, a new 14-membered resorcylic acid lactone, has been synthesized from inexpensive and commercially available starting materials. This convergent synthesis utilizes Cross metathesis using the Grubbs Hoveyda catalyst, alkylation of 1,3-dithiane and Yamaguchi macrolactonization as key steps. 相似文献
82.
Lakshmi Narayana Sharma Konidena Suresh Kumar Chettu Praveena Mukkavilli Krishna Reddy Valluru Kameswara Rao N.S. Annapurna Nowduri Raghu Babu Korupolu 《中国化学会会志》2019,66(2):226-230
A new total synthesis of [R]‐Patulolide A from readily available (R)‐propylene epoxide obtained using the asymmetric synthetic approach is reported. The key reactions involved are ozonolysis and Yamaguchi macrolactonization, resulting in the ring system. 相似文献
83.
Rajender Datrika Srinivasa Reddy Kallam Siddaiah Vidavalur Nagaraju Rajana 《Tetrahedron》2019,75(19):2824-2831
The formal synthesis of Cladospolide-C and its analog is achieved by using enantiopure (R)-γ–valerolactone 10. The significant points of this synthesis are the stereoselective dihydroxylation of α, β-unsaturated ester 16 using Sharpless protocol, Wittig olefination of γ –valerolactol 6 with triphenylphosphonium iodide salt 7, one pot selective oxidation of 22 and subsequent C2-homologation with good E/Z ratio. 相似文献
84.
The first stereoselective total synthesis of nonenolide (?)-stagonolide D has been accomplished. Midland Alpine borane reduction to install hydroxyl group at C4, Henbest epoxidation to introduce epoxide stereoselectively between C7 and C8, Yamaguchi esterification and Olefin metathesis reaction are the key steps involved in the total synthesis. 相似文献
85.
Baggu Chinnababu Sudina Purushotham Reddy Kunuru Venkatesham Dasireddi Chandra Rao Yenamandra Venkateswarlu 《Helvetica chimica acta》2014,97(5):613-618
A simple and highly efficient synthetic route has been developed for synthesis of 1‐(4‐hydroxyphenyl)nonadecane‐3,5‐diol ( 1 ). The two stereogenic centers were generated by employing proline asymmetric α‐hydroxylation (MacMillan α‐hydroxylation), Jacobsen's hydrolytic kinetic resolution (HKR), and, finally, Yamaguchi oxirane opening as key steps (Scheme 2). 相似文献
86.
Herein we document the first total synthesis of mangiferaelactone and thus establish its absolute configuration. The central nonenolide ring was constructed using ring closing metathesis and Yamaguchi esterification. The key alcohol fragment was synthesized by the Bernet–Vasella fragmentation of C-ribofuranoside. 相似文献
87.
Palakodety Radha Krishna Ramesh Kunde Rajesh Nomula Kallaganti V.S. Ramakrishna 《Tetrahedron letters》2014
Total synthesis of the proposed structure of xylogiblactone B is described using d-(+)-mannitol, regioselective epoxide ring-opening, Yamaguchi esterification, and ring-closing metathesis as key steps. 相似文献
88.
Electrophilic cyclizations of unactivated alkenes play highly important roles in the synthesis of useful building blocks. This account describes our contributions to the rational design of monofunctionalized chiral Lewis base catalysts for enantioselective iodo‐ and protocyclizations. For the stereoselective promotion of electrophilic bromocyclizations, nucleophilic phosphite–urea cooperative catalysts have been designed. 相似文献
89.
《Magnetic resonance in chemistry : MRC》2002,40(8):533-536
Determination of the level and absolute configuration of 2‐hydroxyglutaric acid in a patient's urine is a method of diagnosing two metabolic diseases. Such a determination can be done with the aid of NMR spectroscopic methods. In this paper the careful interpretation of 1H and 13C NMR spectra of this metabolite and its lactone measured under conditions used in biomedical assays is reported. The 1H chemical shifts and spin–spin coupling constants were derived using the total lineshape analysis method. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
90.
Synthesis of the polyoxygenated nonalactone ring of 2-epibotcinolide was achieved using a highly stereoselective aldol reaction of the titanium enolate from a lactate-derived chiral ketone, a stereoselective dihydroxylation and a Yamaguchi macrolactonization reaction. 相似文献