289-06-5 Usage
Description
1,3,4-Thiadiazole is a five-membered, aromatic, weakly basic, planer, electron-deficient, conjugated heterocyclic ring system comprised of two carbon atoms, one sulfur atom, and two pyridine-like nitrogen atoms present at the 3- and 4-positions of the ring. The dipole moment (3.25 D) for 1,3,4-thiadiazole suggests that it is a polar symmetric molecule with pseudo-aromatic character. The carbon atoms at the 2- and 5-positions are electron deficient because of the inductive effect of nitrogen and sulfur and thus they are inert toward electrophilic substitution but reactive toward nucleophilic attack.
Uses
1,3,4-Thiadiazole, a bioisostere of the thiazole ring, has been used in the synthesis of cephalosporine and cefazedone, which are used as antibiotics. Megazole is another 1,3,4-thiadiazole-based drug, widely used in the treatment of African trypanosomes, also known as sleeping sickness. Azetepa, a phosphoruscontaining drug, has been used for the treatment of cancer. Tebtheuron is known as a broad-spectrum herbicide and is used to control a variety of weeds and herbaceous and woody plants. Numerous thiadiazole derivatives are patented as bactericides, insecticides, and fungicides.
Chemical Reactivity
Atomic charges have been calculated by the DFT method. The maximum charge was found at the S atom (0.818) and thus it is the favorite position for soft nucleophilic attack. The atomic charge on each carbon is ?0.3275. Because of the presence of the two pyridine-like nitrogen atoms in the ring, which make the C2 - and C5 -positions electronically poor, nucleophilic substitution of the leaving groups present at either the C2 - or C5 -position becomes highly facile. However, the atomic charge on N3 and N4 (?0.0308) makes them preferential sites for electrophilic attack and readily N-alkylated or N-acylated. In strongly basic conditions the thiadiazole ring leads to ring fission.
Biological Activity
Anti-inflammatory,antivira and antimicrobial.
Check Digit Verification of cas no
The CAS Registry Mumber 289-06-5 includes 6 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 3 digits, 2,8 and 9 respectively; the second part has 2 digits, 0 and 6 respectively.
Calculate Digit Verification of CAS Registry Number 289-06:
(5*2)+(4*8)+(3*9)+(2*0)+(1*6)=75
75 % 10 = 5
So 289-06-5 is a valid CAS Registry Number.
InChI:InChI=1/C2H2N2S/c1-3-4-2-5-1/h1-2H
289-06-5Relevant articles and documents
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Sbrana,Ginanneschi
, p. 517,520,522 (1966)
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Thiadiazoles and oxadiazoles and their use as phosphodiesterase-7 inhibitors
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, (2008/06/13)
The invention provides 1,3,4-thiadiazoles and 1,3,4-oxadiazoles having the following Formula I: in which, Y is S or O, R1 is alkyl, alkenyl, alkynyl, cycloalkyl, heterocycloalkyl, cycloalkenyl, aryl, heteroaryl or a polycyclic group, optionally substituted, R2 is alkyl, alkenyl, alkynyl, cycloalkyl, heterocycloalkyl, cycloalkenyl or aryl optionally substituted, R3 is X2—R′3, in which X2 is a binding group and R′3 is cycloalkyl, heterocycloalkyl, cycloalkenyl, aryl, heteroaryl, or a polycyclic group; optionally substituted, or their pharmaceutically acceptable derivatives, a compound of Formula I, for their preparation, and processes for pharmaceutical compositions containing methods of using the compounds for the treatment of disorders for which a treatment by a PDE7 inhibitor is relevant.
Trisubstituted heterocyclic compounds and their use as fungicides
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, (2008/06/13)
Compounds of general formula (I): in which:Het represents a five or six membered saturated, partially unsaturated or aromatic ring containing between one and six heteroatoms of the group N, O, S, in which the heterocycle is substituted in an adjacent manner with -P-Q1-T-Q2, -GZ and Y, such that the substituant -GZ is adjacent to both. the other substituants being as defined in the description,process for preparing these compounds,fungicidal compositions comprising these compounds,processes for treating plants by applying these compounds or compositions.
