Synthesis And Research Of TetrahydroPyrido Thieno Pyrimidin-4(3H)-One Derivatives

Many azole compounds have been found to show widespread biological activities. Some of them have been used as fungicide, herbicide, pesticide and medicine .In this paper, a new synthetic method to 2-substituted -5,6,7,8-tetrahydropyrido[3' ,4' :5,4] thieno [2,3-d] pyrimidin-4 (3H)-one derivatives was proposed. This synthetic method has the advantage of easily accessible starting material, mild condition and good yields. The reactions of aza-Wittig were studied further. The spectral properties were also researched and some of them were found to show good fungicidal activities. More than forty unreported compounds in four parts were synthesized, it may be summarized as follows:1. 1,5-diphenylpenta-1,4dien-3-one is synthesized using Claisen-Schmidt reaction.2. 1-methyl-2,6-diphenylpiperidin-4-one is synthesized using 1,5-diphenylpenta-1,4-dien-3-one and methylamine3. Gewald reaction was utilized to obtain ethyl 2 -amino -6-methyl -5,7-diphenyl -4,5,6,7- tetrahydrothieno pyridine -3- carboxylate4. Had synthesized iminophosphorane as an important intermediate.5. The iminophosphorane reacted with aryl isocyanates to give carbodimide as actived intermediate.6. The carbodimide reacted with second amines and primary amines to give 2-alkylamino -3-aryl-7- methyl -6,8- diphenyl -5,6,7,8- tetrahydropyrido[3' ,4 :5,4] thieno [2,3-d] pyrimidin - 4(3H)-one derivatives via aza-Wittig reaction catalyzed by NaOEt7. The carbodimide reacted with alcohols to give 2-alkyloxyl-3-aryl -7- methyl- 6,8-diphenyl -5,6,7,8-tetrahydropyrido[3' ,4' :5,4] thieno [2,3-d] pyrimidin - 4(3H)-one derivatives via aza-Wittig reaction catalyzed by NaOEt8. The carbodimide reacted with phenols to give 2-aryloxyl-3-aryl -7- methyl -6,8-diphenyl -5,6,7,8- tetrahydropyrido [3,4'.5,4] thieno [2,3-d] pyrimidin - 4(3H)-one derivatives via aza-Wittig reaction catalyzed by solid K2CO3.9. The cyclization of carbodiimide with second amines and alcohols was in presence of sodium alkoxide .But the cyclization of carbodiimide with phenols was in presence of solid potassium carbonate.