CYCLIC PHENYLBORONATES OF ECDYSTEROIDS AS PRODUCTS OF REGIOSPECIFIC REACTION WITH PHENYLBORONIC ACID

Authors
PIS J HYKL J BUDESINSKY M HARMATHA J
Citation
J. Pis et al., CYCLIC PHENYLBORONATES OF ECDYSTEROIDS AS PRODUCTS OF REGIOSPECIFIC REACTION WITH PHENYLBORONIC ACID, Collection of Czechoslovak Chemical Communications, 58(3), 1993, pp. 612-618
Citations number
10
Categorie Soggetti
Chemistry
Journal title
Collection of Czechoslovak Chemical Communications → ACNP
ISSN journal
00100765
Volume
58
Issue
3
Year of publication
1993
Pages
612 - 618
Database
ISI
SICI code
0010-0765(1993)58:3<612:CPOEAP>2.0.ZU;2-9
Abstract
The diol system in the side-chain of ecdysteroids reacts with phenylbo ronic acid under formation of cyclic esters. Phenylboronates of ecdyst eroids I - V were prepared. The regiospecific reaction course was conf irmed by H-1 NMR spectra of the products. The reaction conditions were studied for 20-hydroxyecdysone (1). The phenylboronate can be prepare d in high yields even in aqueous solutions. The liberation of the ecdy steroid I from the corresponding phenylboronate VI was performed using various reagents - diols or carboxylic acids.