Photocyclization of enamides. XXXII. Alkaloid synthesis using furopyridone as a synthon: Synthesis of key intermediates for the synthesis of (.+-.)-quinine, (.+-.)-ajmalicine, and (.+-.)-7-demethyltecomanine.
Furopyridones 4a-c were shown to be available as synthons for alkaloid synthesis by their facile conversion to the key intermediates 13a, b, and 16 for the synthesis of quinine, ajmalicine, and 7-demethyltecomanine.
hyl groups in the furan ring have been synthesized via the Arbuzov reaction from the corresponding acid chlorides. NMR spectral parameters of the prepared compounds were studied. The values of coupling constants between the phosphorus nuclei and the carbon nuclei of the furan ring have been examined with relation to the location of the acylphosphoryl group in the furan ring, the nature of second substituent
1-(3-Phenylpropyl)-4-furoylpiperazine represented by the following general formula (I), ##SPC1## (wherein: R.sub.1 and R.sub. 2, which may be the same or different, each represents a hydrogen atom or a lower alkyl group containing 1 to 4 carbon atoms; R.sub.3 represents a hydrogen atom, a halogen atom, a lower alkyl group containing 1 to 4 carbon atoms, or a lower alkoxy groups containing 1 to 4 carbon atoms; R.sub.4 and R.sub.5, which may be the same or different, each represents a hydrogen atom or a lower alkyl group containing 1 to 4 carbon atoms), and pharmaceutically acceptable addition salts thereof.
Compounds of the formula ##STR1## where A, B, E and D have the meanings indicated in the description, and their preparation are described. The substances are suitable for controlling diseases.
A photoresist composition which is particularly useful as a chemical amplification type photoresist is provided, wherein the photoresist composition contains a resin having a structural unit represented by the following formula (I) :
wherein R1, R2 and R3 each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; R4 represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms and R5 represents a hydrogen atom, alkyl group or aryl group, or R4 and R5 join together to form a ring, which may be heterocyclic; and R6 represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms or a hydroxyl group.