الفهرس 
Introductionيوجد فقط 14 صفحة متاحة للعرض العام
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المستخلص
Convenient and efficient methods in the synthesis of new heterocycles from the reactions of organic moieties containing polar functional groups with 7T:-deficient compounds
The aim of this study is the synthesis of prospective biological and pharmaceutical new heterocyclic compounds via the reaction of electron donors with some 1t-<leficient compounds. The electron donors used in this study are in (Fig. I):
1. Diaroyl sulfides la-c.
2. (Ylidene )hydrazinecarbothioamides 2a-r.
3. Carbamodithioate salts 3a-e.
4. Bis(dithiocarbamate) salt 4.
5. 2,3-Diamino-I,4-naphthoquinone (5).
Convenient and efficient methods in the synthesis of new heterocycles from the reactions of organic moieties containing polar functional groups with n:-deficient compounds
Convenient and efficient m organic moieties containing
The carbanion formed by this nucleophilic attack can abstract a proton from the reaction medium to give intermediate 16 in addition to ethyl aryloate. Ethanol presumably removes an aroyl group from 15 in the form of ethyl aryloate as opposed to a free aroyl cation. Subsequently another molecule of I would add to 16 to form the stable products 14a-c together with a second molecule of ethyl aryloate (Scheme 2).
A mixture of equimolar for 13-16 h, afforded (S)-(1 scheme 5.
(S,SH I ,4-Dioxo-1 ,4-diphenylbutane-2,3-diyl)diaroyIcarbothioates 17a-c were isolated from the reaction of la-c and 1,4-diphenylbut-2-yne-l,4-dione (7) in ethanol under reflux conditions (Scheme 3).
o 0
+ Ph-g-C:=C-g-Ph Ethanol (abs.). reflux, 2-6 h
Refluxing equimolar dimethyl acetylenedicarbm.;y 20a-r (Scheme 6).
Ethyl (2Z)-3-(aroylthio)acrylate 18a-c were isolated from the reaction of diaroyl sulfides la-c with ethyl propiolate (8) in refluxing ethanol (Scheme 4).
RyO
Ethanol (abs.) s~ ,ellu,. 3-6 h • C,”,oy
o 18a-c
Convenient and efficient methods in the synthesis of new heterocycles from the reactions of organic moieties containing polar functional groups with n:-deficient compounds
I group another olecule
A mixture of equimolar amounts of la-c and 9 in absolute ethanol was heated under reflux for 13-16 h, afforded (S)-(l-benzoyl-3-oxo-3-phenylpropyl)aroylcarbothioates 19a-c as shown in scheme 5.
1.5, Reactions of substituted (ylidene)hydrazinecarbothioamide 2a-r with dimethyl acetylenedicarboxylate (DMAD, 6)
Refluxing equimolar amounts of substituted (ylidene )hydrazinecarbothioamide 2a-r and dimethyl acetylenedicarboxylate (6) for 0.5-2 h, in methanol, afforded thiazin-4-one derivatives 20a-r (Scheme 6).
2 and 20: a, R = CsHs-, R’ = CsHs-CH=CH- (trans); b, R = CsHsCH2-, R’ = CsHs-CH=CH- (trans);
c, R = CH2=CH-CH2-, R’ = CsHs-CH=CH- (trans); d, R = CsHs-, R’ = 2-CH30-CsH4-CH=CH- (trans);
e, R = CsHsCH2-, R’ = 2-CH30-CsH4-CH=CH- (trans);
f, R = CH2=CH-CH2-, R’ = 2-CH30-CsH4-CH=CH- (trans); g, R = CsHs-, R’ = CsHs-CH=C(CH3)- (trans);
h, R = CsHs-, R’ = CH3-(CH2h-CH=CH- (trans);
i, R = CsHsCHr, R’ = CH3-(CH2h-CH=CH- (trans);
j, R = CH2=CH-CH2-, R’ = CH3-(CH2h-CH=CH- (trans); k, R = CsHs-, R’ = CH3-CH=CH-(trans);
I, R = CsHsCH2-, R’ = CH3-CH=CH- (trans);
m, R = CH2=CH-CH2-, R’ = CH3-CH=CH- (trans); n, R = CsHs-, R’ = (CH3hCH-;
0, R = CsHsCH2-, R’ = (CH3)2CH-;
p, R = CH2=CH-CH2-, R’ = (CH3hCH-; q, R = CsHs-, R’ = C2Hs-CH(CH3)-;
r, R = CsHs-, R’ = CH3-(CH2)a-