- Bicycloocta-1,5-diene-3,7-dione
-
Bicycloocta-1,5-diene-3,7-dione (5) has been prepared by the hydrolysis-decarboxylation of tetramethyl 3-hydroxy-7-oxobicycloocta-1,3,5-triene-2,4,6,8-tetracarboxylate sodium salt (2), which was obtained in one step from "Vossen's Red Salt" (1).
- Docken, Adrian M.
-
-
Read Online
- A synthetic approach to 5/5/6-polycyclic tetramate macrolactams of the discodermide type
-
A flexible synthetic route to the 16-membered tetramate-embedding macrocyclic scaffold present in various polycyclic tetramate macrolactams (PTMs) was developed which differs from the seminal synthesis of ikarugamycin by Boeckman Jr. in protecting groups and the order of connections. We also devised a short approach to various stereoisomers of the 5/5/6-tricarbocyclic motif found in discodermide and other PTMs, starting from the Weiss’ diketone.
- Bodenschatz, Kevin,St?ckl, Julia,Winterer, Markus,Schobert, Rainer
-
-
- DIHYDROPTERIDINONE DERIVATIVES, PREPARATION PROCESS AND PHARMACEUTICAL USE THEREOF
-
Dihydroperidinone derivatives, preparation process and pharmaceutical use thereof are disclosed. Specially, new dihydroperidinone derivatives represented by general formula (I), wherein each substituent of the general formula (I) is defined as in the description, their preparation process, pharmaceutical compositions comprising said derivatives and their use as therapeutical agents, especially as Plk kinase inhibitors are disclosed.
- -
-
Page/Page column 43
(2012/08/08)
-
- DIHYDROPTERIDINONE DERIVATIVES, PREPARATION PROCESS AND PHARMACEUTICAL USE THEREOF
-
Dihydroperidinone derivatives, preparation process and pharmaceutical use thereof are disclosed. Specially, new dihydroperidinone derivatives represented by general formula (I), wherein each substituent of the general formula (I) is defined as in the description, their preparation process, pharmaceutical compositions comprising said derivatives and their use as therapeutical agents, especially as Plk kinase inhibitors are disclosed.
- -
-
Page/Page column 46
(2012/07/28)
-
- Versatile Route to centro-Substituted Triquinacene Derivatives: Synthesis of 10-Phenyltriquinacene
-
(Equation Presented) A versatile route to prepare centro-substituted triquinacene derivatives (1, R = various substituents), as exemplified by the preparation of 10-phenyltriquinacene (1, R = Ph), is reported. The quaternary, centro substituent (C-10) was installed by a trimethylsilyl chloride-promoted conjugate addition reaction of an organocuprate, derived from phenylmagnesium bromide, and the protected bicyclic enone (11). The resultant trimethylsilyl enol ether was then converted regioselectively to the C-2-allylated conjugate addition products (13, R = Ph). The allyl moiety, following oxidative cleavage of the carbon-carbon double bond, was used to elaborate the tricyclic ring system by an intramolecular aldol/ acetal deprotection reaction. The product of this reaction was then converted to the target compound using a standard series of functional group transformation reactions.
- Cadieux, Jay A.,Buller, Donovan J.,Wilson, Peter D.
-
p. 3983 - 3986
(2007/10/03)
-
- The first total synthesis of (±)-1-desoxyhypnophilin
-
The paper describes the first total synthesis of (±)-1-desoxyhypnophilin, a linear triquinane from the East African mushroom Lentinus crinitus which displays promising antimicrobial activity. A key feature is the use of a ring closing metathesis reaction with a tertiary allylic alcohol, in conjunction with a PCC induced oxidative rearrangement, to construct a cyclopentenone.
- Harrowven, David C,Lucas, Matthew C,Howes, Peter D
-
p. 9157 - 9162
(2007/10/03)
-
- General Approach to the Synthesis of Polyquinenes via the Weiss Reaction. 6. Progress toward the Synthesis of Dicyclopentapentalenes
-
The synthesis of the three tetraquinanes tetracyclo4,11.06,10>dodecanetetraol (27), tetracyclo2,6.09,13>tetradecanediol (36), and tetracyclo2,6.010,14>tetradecanediol (39) has been achieved via the Weiss reaction.Reaction of glyoxal (4a) with di-tert-butyl 3-oxoglutarate (5b) gave tetra-tert-butyl 3,7-dioxo-cis-bicyclooctane-2,4,6,8-tetracarboxylate (6b) in excellent yield.This was converted, regiospecifically, into bisenol ether 20b with diazomethane.The bisalkyllation of 20b was effected with allyl iodide/KH to provide a mixture of the 2,6-diallyl regioisomer 23b (64percent) and the corresponding 2,8-diallyl dione 24b (36percent); the former compoud crystallized from the reaction mixture.Hydrolysis of teraester 23b furnished 2,6-diallyl dione 7, which was oxidized and cyclized to diketo diol 26, isolated as a mixture of diexo and diendo stereoisomers 26a and 26b, both of which were reduced with borane-tetrahydrofuran to provide the desired tetraol 27 in 80percent yield.The HMPA-mediated dehydration of 27 gave the tetracyclotetradecadiene 28.Furthermore, the 2,6-diallyl diones 7a and 7b were converted with HBr-peroxides into dibromides 35a,b, and this mixture of epimers was cyclized to the tetracyclotetradecanediol 36 on stirring with samarium diiodide (80percent yield).Analogous to the chemistry developed for preparation of 36, the 2,8-diallyl tetra-tert-butyl ester 24b was converted into the 2,8-bis(3-bromopropyl) dione 38, which cyclized on treatment with SmI2 to the desired tetracyclic tetradecanediol 39 in 69percent yield.
- Lannoye, G.,Sambasivarao, Kotha,Wehrli, S.,Cook, J. M.,Weiss, U.
-
p. 2327 - 2340
(2007/10/02)
-
- REACTION OF DIMETHYL SODIO-3-KETOGLUTARATE WITH GLYOXAL AND SUBSTITUTED GLYOXALS; FIRST EXPEDITIOUS PREPARATION OF BICYCLOOCTANE-3,7-DIONE; SYNTHESIS AND CRYSTAL STRUCTURE OF 5,7-DIHYDROXY-4-METHOXYCARBONYL-3-PHENYL-1-INDANONE
-
A simple and efficient two-step preparation of bicyclooctane-3,7-dione starting from the sodium enolate of dimethyl 3-ketoglutarate and glyoxal is described.This is an unprecedented case in which a condensation reaction of glyoxal is more successful under vigorous conditions (refluxing methanol) than under much milder ones (buffered water at ambient temperature).The major product (after hydrolysis-decarboxylation) from the analogous sequence with phenylglyoxal is 5,7-dihydroxy-4-methoxycarbonyl-3-phenyl-1-indanone, the result of a Dieckmann reaction in addition to the Michael and aldol reactions.Only the latter two occur in aqueous buffers, where the product after hydrolysis-decarboxylation is 1-phenylbicyclooctane-3,7-dione.The X-ray crystal structure of the indanone reveals a novel hydrogen bonding phenomenon.
- Bertz, Steven H.,Rihs, G.,Woodward, R.B.
-
-
- General approach for the synthesis of polyquinanes. Facile generation of molecular complexity via reaction of 1,2-dicarbonyl compounds with dimethyl 3-ketoglutarate
-
The condensation of dimethyl 3-ketoglutarate 1 with 1,2-dicarbonyl compounds provides access to the polyquinane derivatives tricyclo[6.3.0.01,S]undecane-3,7,9-trione 27, tricyclo[3.3.3.01,s]undecane 31; tetra-cyclo[5.5.1.04,13.010,13]-tridecane-2,6,8,12-tetraone 41; tetracycloI6.6.0.0u.0,l3ltetradecane-2,7,9,14-tetraone 44; and the tetracyclo(5.5.1.01013]tridecane triones Sb and 6b. The unique structure of staurane tetraone 41 has resulted in spontaneous resolution of the two antipodes on crystallization from DMF. In addition, examination of the crystal structures of tetraones 41 and 44, in terms of strain energy, coupled with the steric accessibility of the /5-diketone functionality contained in 41 and 44 have been employed to explain why tetraone 44 and trione 27 undergo a retro-Claisen reaction (CH3OH) more rapidly than staurane tetraone 41.
- Mitschka,Oehldrich,Takahashi,Cook,Weiss,Silverton
-
p. 4521 - 4542
(2014/12/10)
-