137-30-4

Basic information

• Product Name: Zinc bis dimethyldithiocarbamate
• Synonyms: THIONIC;POMARSOL Z;POMARSOL Z(R);MILBAM(R);ZIRAM;ZIRBEK(R);ZINC ME2DTC;ZERLATE(R)
• CAS NO: 137-30-4
• Molecular Formula: C₆H₁₂N₂S₄Zn
• Molecular Weight: 305.829
• EINECS: 205-288-3
• Product Categories: Organometallics;FUNGICIDE;Analytical Chemistry;Classes of Metal Compounds;Environmental Endocrine Disruptors;Estradiol, etc. (Environmental Endocrine Disruptors);Transition Metal Compounds;Zn (Zinc) Compounds;2000/60/EC;Alphabetic;DithiocarbamatesPesticides&Metabolites;European Community: ISO and DIN;Fungicides;OthersAnalytical Standards;Pesticides;ZMethod Specific
• Mol File: 137-30-4.mol
• Article Data: 4

Chemical Properties

• Melting Point: 248-257 °C(lit.)
• Boiling Point: 129.4 °C at 760 mmHg
• Flash Point: 32 °C
• Appearance: /Powder
• Density: 1.66
• Vapor Pressure: <1 x 10-6 Pa
• Storage Temp.: APPROX 4°C
• Water Solubility: 0.0065 g/100 mL
• Merck: 14,10172
• BRN: 3707008
• CAS DataBase Reference: Zinc bis dimethyldithiocarbamate(CAS DataBase Reference)
• NIST Chemistry Reference: Zinc bis dimethyldithiocarbamate(137-30-4)
• EPA Substance Registry System: Zinc bis dimethyldithiocarbamate(137-30-4)

Safety Data

• Hazard Codes: T+,N
• Statements: 22-26-37-41-43-48/22-50/53
• Safety Statements: 22-26-28-36/37/39-45-60-61
• RIDADR: UN 2811 6.1/PG 2
• WGK Germany: 3
• RTECS: ZH0525000
• TSCA: Yes
• HazardClass: 6.1
• PackingGroup: II
• Hazardous Substances Data: 137-30-4(Hazardous Substances Data)

Usage

Description

Zinc bis dimethyldithiocarbamate, also known as Ziram, is a dithiocarbamate salt that is the zinc salt of dimethyldithiocarbamic acid. It is a broad-spectrum fungicide and bird and animal repellent that is also used to accelerate the vulcanization of rubber. It is white and odorless when pure, and has chemical properties that make it almost insoluble in water but soluble in acetone, carbon disulfide, chloroform, dilute alkalies, and concentrated hydrochloric acid.

Uses

Used in Agriculture:
Zinc bis dimethyldithiocarbamate is used as a fungicide for controlling fungal diseases on a wide range of crops, including stone fruits, pome fruits, nut crops, vegetables, and commercially grown ornamentals. It is also used as a soil and seed treatment, and as a bird and rabbit repellent for outdoor foliar applications to ornamentals. It is registered for use in both EU countries and the U.S.
Used in Rubber Industry:
Zinc bis dimethyldithiocarbamate is used as a vulcanization accelerator in the rubber industry, helping to speed up the process of rubber vulcanization and improve the properties of the final product.
Used as a Wildlife Repellent:
Zinc bis dimethyldithiocarbamate is used as a paste or spray to repel birds and animals from tree trunks, ornamentals, dormant fruit trees, and other crops, providing an effective method of protecting plants from damage caused by these creatures.

Air & Water Reactions

Thio and dithiocarbamates slowly decompose in aqueous solution to form carbon disulfide and methylamine or other amines. Such decompositions are accelerated by acids. Insoluble in water.

Reactivity Profile

Zinc bis dimethyldithiocarbamate is a dithiocarbamate. Flammable gases are generated by the combination of thiocarbamates and dithiocarbamates with aldehydes, nitrides, and hydrides. Thiocarbamates and dithiocarbamates are incompatible with acids, peroxides, and acid halides. Zinc bis dimethyldithiocarbamate is corrosive to iron and copper. Zinc bis dimethyldithiocarbamate is incompatible with strong oxidizing agents and acids. Zinc bis dimethyldithiocarbamate is also incompatible with mercury.

Hazard

Strong irritant to eyes and mucous membranes.

Fire Hazard

Zinc bis dimethyldithiocarbamate is combustible. Zinc bis dimethyldithiocarbamate may form explosive dust-air mixtures.

Flammability and Explosibility

Notclassified

Trade name

AAPROTECT?; AAVOLEX?; AAZIRA?; ACCELERATOR?-L; ACCELERATOR? MZ? Powder; ACETO ZDED?; ACETO ZDMD?; ALCOBAM ZM?; ANCANZATE ME?; CARBAZINC?; CIRAM?; CORONA COROZATE?; COROZATE?; CUMAN?; CUMAN L?; CYMATE?; DRUPINA? 90; EPTAC-1?; FUCLASIN?; FUCLASIN? ULTRA; FUKLASIN?; FUNGOSTOP?; HERMAT ZDM?; HEXAZIR?; KARBAM WHITE?; KYPZIN?; METHASAN?; METHAZATE?; MEXENE?; MEZENE?; MILBAM?; MILBAN?; MOLURAME?; MYCRONIL?; OCTOCURE ZDM-50?; ORCHARD? BRAND ZIRAM; PERKACIT ZDMC?; POMARSOL? Z FORTE; PRODARAM?; PROKIL? Ziram; RHODIACID?; SOXINAL?-PZ; SOXINOL?-PZ; TRICARBAMIX Z?; TSIMAT?; TSIRAM? (Russian); ULTRA ZINC DMC?; VANCIDE? MZ-96; VANCIDE? 51Z Dispersion (with Zinc 2-mercaptobenzothiazolate); VANCIDE? 51Z Dispersion (with Ziram); ZERLATE?; ZINCMATE?; ZIMATE?; ZIMATE?; METHYL?; ZIRAMVIS?; ZIRASAN?; ZIRBERK?; ZIREX 90?; ZIRIDE?; ZIRTHANE?; ZITOX?

Contact allergens

Ziram is a rubber vulcanization accelerator of the dithiocarbamate group. Sensitization was reported in several patients. Ziram is also used as a fungicide and can cause contact dermatitis in agricultural workers.

Safety Profile

Poison by ingestion,intraperitoneal, and intravenous routes. Moderately toxicby inhalation. Questionable carcinogen with experimentalcarcinogenic and tumorigenic data. An experimentalteratogen. Other experimental reproductive effects.Human mutation d

Metabolic pathway

Ziram is one of the metal containing dithiocarbamates which generates dimethyldithiocarbamic acid by being cleaved in acidic conditions and in biological media. The resulting acid is conjugated with glucose and alanine in plants and with glucuronic acid in mammals. Dimethyldithiocarbamic acid is further degraded to dimethylamine and CS2. An extensive review of the properties of dithiocarbamate pesticides was published by the World Health Organisation (WHO, 1988) from which much of the following information is taken.

Purification Methods

Crystallise this herbicide several times from hot toluene or from hot CHCl3 by addition of EtOH. [Beilstein 4 III 149, 4 IV 234.]

Degradation

Ziram is decomposed in acidic media and by UV irradiation (PM). Ziram is stable in alkaline media but unstable in acidic conditions, decomposing to dimethylamine and carbon disulfide.

InChI:InChI=1/2C3H7NS2.Zn/c2*1-4(2)3(5)6;/h2*1-2H3,(H,5,6);/q;;+2/p-2/rC6H12N2S4Zn/c1-7(2)5(9)11-13-12-6(10)8(3)4/h1-4H3

Synthetic route

Thiram (137-26-8) + zinc (7440-66-6) → bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4)

Conditions	Yield
In acetonitrile Electrolysis; 4 h, initial voltage 10 V, Zn anode; product was collected, washed with acetonitrile and then petroleum ether and dried in vacuo; elem. anal.;	>99

zinc(II) chloride (7646-85-7) + sodium dimethyldithiocarbamate (128-04-1) → bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4)

Conditions	Yield
In water byproducts: NaCl; ZnCl2, the thiocarbamate in water, immediately pptn.; filtered hot to remove NaCl and any excess of unreacted thiocarbamate, dried (vac. at 80°C), recrystn. (boiling benzene);
In ethanol ZnCl2 is dissolved in the minimum quantity of ethanol; addn. of a saturated ethanolic soln. of organic compound.; pptn., filtn., washing (ethanol);
In water

carbon disulfide (75-15-0) + dimethyl amine (124-40-3) + zinc(II) chloride (7646-85-7) → bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4)

Conditions	Yield
In acetone direct reaction of ZnCl2 with dimethylamine and carbon disulfide in acetone;

bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) + tetra(n-butyl)ammonium benzoxazole-2-thiolate (75593-47-4) → tetra-n-butylammonium (benzoxazole-2-thiolato)bis(dimethyldithiocarbamato)zincate

Conditions	Yield
In acetone refluxed for 2 h; cooled, filtered, light petroleum added, crystals filtered off, washed with light petroleum, air dried; elem anal.;	100%

bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) + tetra(n-butyl)ammonium benzothiazole-2-thiolate (55948-28-2) → tetra-n-butylammonium (benzothiazole-2-thiolato)bis(dimethyldithiocarbamato)zincate (75900-13-9)

Conditions	Yield
In acetone refluxed for 1 h; soln. filtered, filtrate partialy evapd., crystals filtered off, recrystd. from ethanol-light petroleum; elem anal.;	100%

2-methyl-4,5-dihydro-1,3-oxazole (1120-64-5) + bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) → [Zn(S2CNMe2-κ(2)S)2(2-methyl-2-oxazoline-κ(1)N)]*H2O

Conditions	Yield
In toluene Zn-complex dissolved in toluene, ligand added, refluxed for 18 h, cooledto room temp.; filtered, evapd. to dryness, washed with Et2O; elem. anal.;	82%

bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) + (S)-(-)-ethyl mandelate (13704-09-1) → ethyl (R)-2-((dimethylcarbamothioyl)thio)-2-phenylacetate

Conditions	Yield
With triphenylphosphine; diethylazodicarboxylate In toluene at 2 - 20℃; for 17h;	81%

bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) + {(CH3CH2CH2CH2)4N}(1+)*{S2COC2H5}(1-)={(CH3CH2CH2CH2)4N}{S2COC2H5} (129117-00-6) → {(CH3CH2CH2CH2)4N}(1+)*{Zn(S2CN(CH3)2)2(S2COC2H5)}(1-)={(CH3CH2CH2CH2)4N}{Zn(S2CN(CH3)2)2(S2COC2H5)}

Conditions	Yield
In acetone addn. of solid (Zn(S2CNMe2)2) in small portions to a soln. of (N-n-Bu4)(S2COEt) in acetone (room temp.), stirring (2 h); filtration, addn. of light petroleum (b.p. 60-80°C), refrigeration (0°C, 2 d), crystn., suction filtration in air, drying, recrystn. (light petroleum/acetone (1:1), room temp.); elem. anal.;	80%

2-ethyl-4,5-dihydrooxazole (10431-98-8) + bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) → [Zn(S2CNMe2-κ(2)S)2(2-ethyl-2-oxazoline-κ(1)N)]

Conditions	Yield
In toluene Zn-complex dissolved in toluene, ligand added, refluxed for 23 h, cooledto room temp.; filtered, evapd., digested in CH2Cl2, filtered, evapd. to dryness; elem.anal.;	40%

bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) + 3-chloro-benzenecarboperoxoic acid (937-14-4) → Zn(N,N-dimethyldithiocarbamato)(O-dmDTC) (906063-87-4)

Conditions	Yield
In chloroform; acetonitrile a soln. of ClC6H4CO3H in CHCl3/MeCN added dropwise to a soln. of Zn complex in CHCl3 at 4°C, stirred for 10-12 h; evapd. (vac.), washed (cold MeCN); elem. anal.;	34%

bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) + tetrabutylammonium decanoate (34283-64-2) → {N(CH2CH2CH2CH3)4}(1+)*{Zn(S2CN(CH3)2)3}(1-) = {N(CH2CH2CH2CH3)4}{Zn(S2CN(CH3)2)3} + zinc(II) decanoate (13040-17-0)

Conditions	Yield
In acetone reflux 2 h;

bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) + Heptanoatetetrabutyl-ammonium; (34283-62-0) → {N(CH2CH2CH2CH3)4}(1+)*{Zn(S2CN(CH3)2)3}(1-) = {N(CH2CH2CH2CH3)4}{Zn(S2CN(CH3)2)3} + zinc(II) heptanoate (5261-20-1)

Conditions	Yield
In acetone reflux 2 h;

2.9-dimethyl-1,10-phenanthroline (484-11-7) + bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) → Zn(S2CNMe2)2(DMP) (120795-84-8)

Conditions	Yield
In methanol; dichloromethane addn. of hot soln. of amine in MeOH to hot soln. of dithiocarbamate in CH2Cl2; cooling, addn. to petroleum ether, pptn., filtration, recrystn. (CHCl3); elem. anal.;

[2,2]bipyridinyl (366-18-7) + bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) → Zn(S2CNMe2)2(bipy) (120831-80-3)

Conditions	Yield
In methanol; dichloromethane addn. of hot soln. of amine in MeOH to hot soln. of dithiocarbamate in CH2Cl2; cooling, addn. to petroleum ether, pptn., filtration, recrystn. (CH2Cl2); elem. anal.;

1,10-Phenanthroline (66-71-7) + bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) → Zn(S2CNMe2)2(phen) (120795-83-7)

Conditions	Yield
In methanol; dichloromethane addn. of hot soln. of amine in MeOH to hot soln. of dithiocarbamate in CH2Cl2; cooling, addn. to petroleum ether, pptn., filtration, recrystn. (MeOH); elem. anal.;

bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) + 3,4,7,8-Tetramethyl-o-phenanthrolin (1660-93-1) → Zn(S2CNMe2)2(TMP) (120795-85-9)

Conditions	Yield
In methanol; dichloromethane addn. of hot soln. of amine in MeOH to hot soln. of dithiocarbamate in CH2Cl2; cooling, addn. to petroleum ether, pptn., filtration, recrystn. (CHCl3); elem. anal.;

bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) + hexanoic acid tetrabutylammonium salt → {N(CH2CH2CH2CH3)4}(1+)*{Zn(S2CN(CH3)2)3}(1-) = {N(CH2CH2CH2CH3)4}{Zn(S2CN(CH3)2)3} + zinc bis(n-hexanoate) (20779-08-2)

Conditions	Yield
In acetone reflux 2 h;

bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) + tetrabutylammonium caprylate → {N(CH2CH2CH2CH3)4}(1+)*{Zn(S2CN(CH3)2)3}(1-) = {N(CH2CH2CH2CH3)4}{Zn(S2CN(CH3)2)3} + zinc(II) octanoate (557-09-5)

Conditions	Yield
In acetone reflux 2 h;

bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) + tetrabutylammonium pelargonate (34283-63-1) → {N(CH2CH2CH2CH3)4}(1+)*{Zn(S2CN(CH3)2)3}(1-) = {N(CH2CH2CH2CH3)4}{Zn(S2CN(CH3)2)3} + zinc(II) nonanoate (7640-78-0)

Conditions	Yield
In acetone reflux 2 h;

bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) + tetrabutylammonium stearate (60080-83-3) → {N(CH2CH2CH2CH3)4}(1+)*{Zn(S2CN(CH3)2)3}(1-) = {N(CH2CH2CH2CH3)4}{Zn(S2CN(CH3)2)3} + zinc stearate (557-05-1)

Conditions	Yield
In acetone reflux 2 h;

bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) + N(CH3)4(1+)*S(S)CN((CH2)3CH3)2(1-)={N(CH3)4}{S(S)CN((CH2)3CH3)2} → bis(N,N'-di-n-butyldithiocarbamato)zinc(II) (136-23-2)

Conditions	Yield
byproducts: [NMe4][S2CNMe2];

bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) + N(CH3)4(1+)*S2CN(C6H11)2(1-)=[N(CH3)4][S2CN(C6H11)2] (75593-55-4) → Zn((C6H11)2NCS2)2 (35091-69-1)

Conditions	Yield
byproducts: [NMe4][S2CNMe2];

bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) + 1-bromo-2,3-dimethyl-2-butene (5072-70-8) → ZnBr2((CH3)2NCS2CH2CH3CC(CH3)2)2*CHCl3

Conditions	Yield
In chloroform addn. of 2 equiv. of tme-Br to chloroform suspn. of Zn(dmtc)2 with stirring (5 min); evapn. of solvent; elem. anal.;

bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) + 1-bromo-2,3-dimethyl-2-butene (5072-70-8) → ZnBr2((2,3-dimethyl-2-butenyl)(dimethyldithiocarbamyl)) (149971-66-4)

Conditions	Yield
In tetrahydrofuran heating Zn(dmtc)2 and tme-Br in THF to 140°C with stirring (1 h); cooling to room temp., removal of solvent and excess of tme-Br under reduced pressure; detn. by (1)H and (13)C-NMR spectroscopy;

bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) + tetramethyl ammonium hydroxide → N(CH3)4(1+)*Zn(S2CN(CH3)2)2(OCOCH3)(1-)=[N(CH3)4][Zn(S2CN(CH3)2)2(OCOCH3)] (75642-74-9)

Conditions	Yield
With acetic acid In acetone (NMe4)OH acetic acid in acetone evapd. to dryness, then added Zn(S2CNMe2)2, then refluxed for 2 h; cooled, filtered, filtrate dried over MgSO4, light petroleum added, precipitated crystals filtered off, washed with light petroleum, dried in vac., elem anal.;

bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) + tetramethyl ammonium hydroxide + propionic acid (802294-64-0) → tetramethylammonium bis(dimethyldithiocarbamato)propionatozincate (75642-72-7)

Conditions	Yield
In acetone (NMe4)OH propionic acid in acetone evapd. to dryness, then added Zn(S2CNMe2)2, then refluxed for 2 h; cooled, filtered, filtrate dried over MgSO4, light petroleum added, precipitated crystals filtered off, washed with light petroleum, dried in vac., elem anal.;

bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) + tetramethyl ammonium hydroxide + butyric acid (107-92-6) → N(CH3)4(1+)*Zn(S2CN(CH3)2)2(OCOCH2CH2CH3)(1-)=[N(CH3)4][Zn(S2CN(CH3)2)2(OCOCH2CH2CH3)] (75642-76-1)

Conditions	Yield
In acetone (NMe4)OH butiric acid in acetone evapd. to dryness, then added Zn(S2CNMe2)2, then refluxed for 2 h; cooled, filtered, filtrate dried over MgSO4, light petroleum added, precipitated crystals filtered off, washed with light petroleum, dried in vac., elem anal.;

bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) + tetramethyl ammonium hydroxide + valeric acid (109-52-4) → N(CH3)4(1+)*Zn(S2CN(CH3)2)2(OCOCH2CH2CH2CH3)(1-)=[N(CH3)4][Zn(S2CN(CH3)2)2(OCOCH2CH2CH2CH3)] (75642-78-3)

Conditions	Yield
In acetone (NMe4)OH pentanonic acid in acetone evapd. to dryness, then added Zn(S2CNMe2)2, then refluxed for 2 h; cooled, filtered, filtrate dried over MgSO4, light petroleum added, precipitated crystals filtered off, washed with light petroleum, dried in vac.;

bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) + tetramethyl ammonium stearate (55489-71-9) → N(CH3)4(1+)*Zn(S2CN(CH3)2)3(1-)=[N(CH3)4][Zn(S2CN(CH3)2)3] (75642-17-0) + zinc stearate (557-05-1)

Conditions	Yield
In acetone reflux 2 h;

bis(dimethylcarbamodithioato-κS,κS')zinc(II) (137-30-4) + tetramethylammonium decanoate (64000-88-0) → N(CH3)4(1+)*Zn(S2CN(CH3)2)3(1-)=[N(CH3)4][Zn(S2CN(CH3)2)3] (75642-17-0) + zinc(II) decanoate (13040-17-0)

Conditions	Yield
In acetone reflux 2 h;

Upstream product

• 75-15-0 carbon disulfide 
• 124-40-3 dimethyl amine 
• 7646-85-7 zinc(II) chloride 
• 128-04-1 sodium dimethyldithiocarbamate 
• 137-26-8 Thiram 
• 7440-66-6 zinc 

Downstream Products

• 13040-17-0 zinc(II) decanoate 
• 5261-20-1 zinc(II) heptanoate 
• 75642-74-9 N(CH₃)4⁽¹⁺⁾*Zn(S₂CN(CH₃)2)2(OCOCH₃)^(1-)=[N(CH₃)4][Zn(S₂CN(CH₃)2)2(OCOCH₃)] 
• 75642-72-7 tetramethylammonium bis(dimethyldithiocarbamato)propionatozincate 
• 75642-76-1 N(CH₃)4⁽¹⁺⁾*Zn(S₂CN(CH₃)2)2(OCOCH₂CH₂CH₃)^(1-)=[N(CH₃)4][Zn(S₂CN(CH₃)2)2(OCOCH₂CH₂CH₃)] 
• 75642-78-3 N(CH₃)4⁽¹⁺⁾*Zn(S₂CN(CH₃)2)2(OCOCH₂CH₂CH₂CH₃)^(1-)=[N(CH₃)4][Zn(S₂CN(CH₃)2)2(OCOCH₂CH₂CH₂CH₃)] 
• 75642-17-0 N(CH₃)4⁽¹⁺⁾*Zn(S₂CN(CH₃)2)3^(1-)=[N(CH₃)4][Zn(S₂CN(CH₃)2)3] 
• 557-05-1 zinc stearate 
• 149971-66-4 ZnBr₂((2,3-dimethyl-2-butenyl)(dimethyldithiocarbamyl)) 
• 7640-78-0 zinc(II) nonanoate 
• 557-09-5 zinc(II) octanoate 
• 20779-08-2 zinc bis(hexanoate) 
• 35091-69-1 Zn((C₆H₁₁)2NCS₂)2 
• 136-23-2 bis(N,N'-di-n-butyldithiocarbamato)zinc(II) 

Relevant articles and documents

Zinc(II) complexes with dithiocarbamato derivatives: Structural characterisation and biological assays on cancerous cell lines

Zinc is one of the most important trace elements in the body and it is essential as a cofactor for the structure and function of a number of cellular molecules including enzymes, transcription factors, cellular signalling proteins and DNA repair enzymes. On the other hand, recent studies have shown that zinc could play a role both in the development of various cancers and in the induction of apoptosis in some cell types, however, no established common relationships of zinc with cancer development and progression have been identified. To date, in our research group different metal-dithiocarbamato complexes have been designed that were expected to resemble the main features of cisplatin together with higher activity, improved selectivity and bioavailability, and lower side-effects. On the basis of the obtained encouraging achievements with other metals (such as gold and copper) we have decided to enlarge the studies to the complexes of zinc(II) using the same ligands. Hereby, we report the results on the synthesis and characterisation of ZnL2 complexes with five different dithiocarbamato derivatives, such as dimethyl-(DMDT), pyrrolidine-(PyDT), methyl-(MSDT), ethyl-(ESDT) and tert-butyl-(TSDT) sarcosinedithiocarbamate. All the obtained compounds have fully been characterised by means of several spectroscopic techniques. In addition, the crystal structure of [Zn(MSDT)2]2 dinuclear complex is also reported. In order to evaluate the in vitro cytotoxic properties, some biological assays have been carried out on a panel of human tumour cell lines sensible and resistant to cisplatin. Some of the tested compounds show cytotoxicity levels comparable or even greater than the reference drug (cisplatin).

Gas-phase electron diffraction study of bis(dimethyldithiocarbamato)copper(II), [Cu(S2CNMe2)2], and bis(dimethyldithiocarbamato)zinc(II), [Zn(S2CNMe2)2]

The molecular structures of [Cu(S2CNMe2)2] and [Zn(S2CNMe2)2] have been studied by gas-phase electron diffraction. Both compounds are monomeric in the gas phase with the metal atoms being bound to two chelating [S2CNMe2] groups (rg(Cu-S) = 2.284 (9) ?; rg(Zn-S) = 2.348 (8) ?). The major difference between the two structures is in the geometry of the MS4 fragments, that of the copper compounds being pseudo square planar (D2h) while that of the zinc compound is pseudotetrahedral (D2d). The reason for the difference is attributed to the availability in the copper(II) compound of crystal field stabilization energy that is greater than the repulsive energy of the steric interactions imposed by the metal adopting a coordination sphere of D2h symmetry. Selected bond lengths and angles in the [S2CNMe2] groups are as follows (the data for the copper compound are quoted first with those for the zinc species being in brackets): rg(C-S) = 1.716 (10) ? [1.727 (10) ?]; rg(C=N) = 1.334 (18) ? [1.351 (17) ?]; rg(C-N) = 1.476 (18) ? [1.479 (17) ?]; ∠αS-M-S(chelate angle) = 78.78 (69)° [79.68 (59)°]; ∠αC=N-C = 124.9 (1.3)° [122.5 (1.2)°].