摘要:
The invention relates to a process for the manufacture of vinylchromanes. This process is concerned with the manufacture of the compounds having the formula ##STR1## wherein R.sup.o is hydrogen or a cleavable protecting group, and comprises cyclizing a compound having the formula ##STR2## wherein R.sup.o is defined above and R.sup.1 is--CH.sub.2 --CH.sub.2 --C(W)(CH.sub.3)--CH.dbd.CH.sub.2 or--CH.sub.2 --CH.sub.2 C(CH.sub.3).dbd.CH--CH.sub.2 --Wwhere W is a leaving group,by means of a chiral transition metal-diphosphine complex.The compounds of formula I are useful intermediates, e.g. in the manufacture of (R,R,R)-.alpha.-tocopherol.
摘要:
There are described compounds of the formula ##STR1## Wherein the variables have been defined herein. The compounds are useful as research tools in the determination of biologically active peptides sequences and also potentially suitable as medicaments, some of them being useful in the prevention or control of the formation of blood platelet thrombi, and some compounds are useful as intermediates.
摘要:
There are described compounds of the formula ##STR1## Wherein the variables have been defined herein. The compounds are useful as research tools in the determination of biologically active peptides sequences and also potentially suitable as medicaments, some of them being useful in the prevention or control of the formation of blood platelet thrombi, and some compounds are useful as intermediates.