摘要:
A process for the synthesis of trans -fused γ -lactones having Formula (IV) from substituted cyclic ketones having Formula (I). A diastereoselective synthesis of (±)- epianastrephin (1) (wherein: R 1 i s ethenyl, R 2 and R 3 is methyl, and n is 1), (±)-anastrephin (2) (wherein: R 2 is ethenyl, R 1 and R 3 is methyl and n is 1), and analogs thereof (wherein :_R 1 is H, C 1-5 alkyl, C 2-6 alkenyl or C 2-6 alkynyl, R 2 is H, C 1-5 alkyl, C 2-6 alkenyl or C 2-6 alkynyl, R 1 and R 2 together with the carbon atom they are attached form a C 3-6 cycloalkyl ring, R 3 is C 1-5 alkyl and n is 0-2): Formula I, II, III, IV.
摘要:
[PROBLEMS] To provide a process for producing optically active hydroxymethylated compounds in high yields at high stereoselectivity with broad substrate generality, and a catalyst for the production. [MEANS FOR SOLVING PROBLEMS] The process comprises reacting a silicon enolate represented by the general formula (1) with formaldehyde in either an aqueous solution or a mixed solvent of water and an organic solvent in the presence of a catalyst obtained by mixing a ligand consisting of a chiral bipyridine or an antipode thereof with Bi(OTf) 3 : (1) wherein R 5 to R 7 are each hydrogen, an aliphatic hydrocarbon group, an aliphatic mono- or poly-cyclic hydrocarbon group, a mono- or poly-cyclic aromatic or araliphatic hydrocarbon group, or a heterocyclic group with the proviso that R 5 and R 7 are different from each other and R 6 is not hydrogen; and R 8 's may be the same or different and are each methyl, ethyl, or isopropyl.
摘要:
The invention disclosed is a composition for conferring low temperature tolerance to agricultural plants which comprises an effective amount of a compound having formula (I). The composition includes compounds, some of which are novel abscisic acid derivatives. Methods of treating plants and plant tissues such as seeds, with compositions according to the invention are also disclosed.
摘要:
New tetra-alkyl-2, 2, 5, 5 cyclohexanone-4 ol-1 and their sulfonated derivatives of the general formula (I), wherein R and R', which may be the same or different, represent an alkyl radical (1-5 atoms of carbon) and R" represents a hydrogen atom or a radical SO2R''' wherein R''' represents an alkyl radical (1-5 atoms of carbon) or an aryl radical (6-14 atoms of carbon), their preparation intermediaries and process, as well as their application to the synthesis of cyclopropanic lactones having the cis structure.
摘要:
The present invention relates to the synthesis of D-chiroinositol from a dialdose, comprising the steps of condensing the dialdose by an acyloin condensation reaction to form an inosose, protecting the carbon atoms at the 2, 3, 4 and 5 positions, reducing the ketone of the inosose and removing the protecting groups. In addition, a method of preparing mannodialdose from mannuronic acid is disclosed.
摘要:
New cyclites with a growth-regulating action, in particular in dicotyledonous plants such as cress, can be isolated from a nutrient solution for streptomycetes.
摘要:
Novel cycloaliphatic anti-androgenic compounds which block androgen receptor sites, with both topical and systemic administration being provided. Pharmaceutical methods are also provided.
摘要:
Die vorliegende Erfindung bezieht sich auf ein Verfahren zur Herstellung eines substituierten Alkylcycloalkanons der Formel (I) umfassend die Alkylierung eines Cycloalkanons der Formel (II) mit einem Alkenderivat der Formel (III), in Gegenwart eines Metalloxids, wobei n 2 bis 20, m 0 bis 10 bedeuten und R eine funktionelle Gruppe ist.
摘要:
The present invention relates to a cyclohexanone derivative of formula (I) in the form of any one of its isomers or mixture thereof. The invention concerns also the preparation and the use of said derivative. The invention's compound is a useful starting material for the preparation of various optically active compounds.