摘要:
There is provided a process for preparing a compound of formula (I)
wherein R is H or a hydroxy protecting group, R₂ is an organic residue and R₃ is H or a nitrogen protecting group, which process comprises reacting together a compound of formula (II)
wherein R₁ is a C₁-C₄ alkyl or a phenyl group, R and R₃ are as defined above, a compound of formula (III)
wherein R₂ is as defined above and X is a cation or a silicon-containing residue, and a salt of a group IIa, IIb or transition element. The compounds of formula (I) are intermediates in the synthesis of penem antibiotics.
摘要:
The present invention relates to a process for the preparation of a compound of the following formula (I)
wherein one of R₁ and R₂ is hydrogen or halogen and the other is independently, an amino group or a C₂-C₄ alkanoyl amino group; R₃ is hydrogen; a linear or branched alkyl, C₁-C₄ alkoxy or C₂-C₄ alkoxycarbonyl group; halogen; or phenyl unsubstituted or substituted by a C₁-C₄ alkyl group; A is a group -(CH₂) n -Het wherein Het is an optionally substituted heteromonocyclic or heterobicyclic ring containing one or two nitrogen atoms and n is zero or an integer of 1 to 3; and the symbol .... ¯ represents a single or double bond and the pharmaceutically acceptable salts thereof. The compounds of the invention can be useful as 5HT3 receptor antagonists.
wherein A is a substituent selected from the group consisting of
wherein R′ is hydrogen or methyl, m is zero or 1 and the means that the azabicyclic rings may be in the α or the β orientation, and the pharmaceutically acceptable salts thereof, are useful in treating CNS disorders, gut motility disorders, and/or emesis, and/or pain in mammals, and/or migraine.
摘要:
The present invention relates to a process for the preparation of exomethylene cephams, which are useful intermediates in the production of many useful β-lactam antibiotics. More particularly there is provided a process for preparing a compound of formula I
wherein n is O or 1, R₁ is hydrogen atom or an organic residue and R₂ is a carboxy protecting group, which process comprises reacting a compound of the formula II
wherein X is halogen atom or acetoxy group and R₁ n and R₂ are as defined above with a lanthanide complex.
摘要:
The present invention relates to a process for the preparation of exomethylene cephams, which are useful intermediates in the production of many useful β-lactam antibiotics. More particularly there is provided a process for preparing a compound of formula I
wherein n is O or 1, R₁ is hydrogen atom or an organic residue and R₂ is a carboxy protecting group, which process comprises reacting a compound of the formula II
wherein X is halogen atom or acetoxy group and R₁ n and R₂ are as defined above with a lanthanide complex.