Nickel(II) thiohydrazide and thiodiamine complexes: Synthesis, characterization, antibacterial, antifungal and thermal studies

Article abstract of DOI:10.1016/j.saa.2007.05.046

Nickel(II) complexes of type [Ni(L)₂Cl₂] and [Ni(L)₂(OCOCH₃)₂], where L = N,N-diphenyl-N-thiohydrazide (L¹) and (N,N-diphenyl-N-thio)-1,3-propanediamine (L²), have been synthesiz

Full text of DOI:10.1016/j.saa.2007.05.046

Available online at www.sciencedirect.com
Spectrochimica Acta Part A 69 (2008) 842–848
Nickel(II) thiohydrazide and thiodiamine complexes: Synthesis,
characterization, antibacterial, antifungal and thermal studies
A.K. Mishra∗, N.K. Kaushik∗
Department of Chemistry, University of Delhi, Delhi 110007, India
Received 28 March 2007; accepted 11 May 2007
Abstract
Nickel(II) complexes of type [Ni(L)2Cl2] and [Ni(L)2(OCOCH3)2], where L = N,N-diphenyl-N-thiohydrazide (L1) and (N,N-diphenyl-N-thio)-
1,3-propanediamine (L2), have been synthesized. The thiodiamines coordinate as a bidentate N–S ligand. The synthesized nickel(II) complexes of
the thiodiamines were characterized by elemental analysis, IR, mass, electronic and 1H NMR spectroscopic and TG/DTA studies. Various kinetic
and thermodynamic parameters like order of reaction (n), activation energy (Ea), apparent activation entropy (S#) and heat of reaction (ꢀH) have
also been carried out for one complex. These complexes were also screened for in vitro antifungal and in vitro antibacterial activities and significant
activity have been found.
© 2007 Elsevier B.V. All rights reserved.
Keywords: Synthesis; Characterization; Thermal; Antifungal; Antibacterial; Spectral
1. Introduction
2. Experimental
There is a considerable interest in the pharmacology of het-
erocyclic ligands and their metal chelates [1–3]. In general,
nitrogen and sulphur containing organic compounds and their
metal complexes display a wide range of biological activity such
as antibacterial, antifungal, antiviral and antitumour [4–7].
The ligands with sulphur, nitrogen and oxygen donor atoms
in their structures can act as good chelating agents for the transi-
tion and non-transition metal ions [8–14]. Coordination of such
compounds with metal ions, such as copper, nickel and iron,
often enhance their activity [15,16], as has been reported for
pathogenic fungi [17]. A few papers have been published on
thetransitionmetalcomplexesofsubstitutedthiosemicarbazides
and thiodiamines [14,18]. In view of number of applications of
thiosemicarbazides, thiodiamines and their complexes we have
synthesized nickel(II) thiodiamine complexes and characterized
byelementalanalysis, IR, mass, electronicand1HNMRspectro-
scopic studies. The synthesized complexes were also screened
for antibacterial and antifungal activities.
All the reagents used were AR grade. The analysis of
CHNS/O contents of ligands and metal complexes were done
on Elementar Analysensysteme Gmbh Vario El-III. IR was
recorded on Perkin-Elmer spectrum 2000 FTIR spectrometer
using KBr dics. Electronic spectra were recorded on Shimadzu
UV–vis spectrophotometer Model 1601 using acetone as sol-
vent. Conductance measurements were carried out on Digital
Conductometer Model PT-827, India using acetone as solvent.
Model Jeol SX102/DA-600 (KV 10MA) was used for recording
Mass spectra of the ligands in acetone solvent. H NMR was
recorded using deuterated acetone on Brucker spectrospin 300
spectrometer.
TG/DTA curves for one complex was recorded on Shimadzu,
model 60 WS Thermal analyzer, in static air at a heating rate of
10 ◦C min−1. The platinum crucible was used with alumina as
the reference material.
1
2.1. Preparation of thiohydrazides and thiodiamines
Kazakova et al. has described the preparation of N,N-
diphenyl-N-thiohydrazide and N,N-thiodiamines. In the present
work, it has been synthesized with some modification from the
method described earlier [10–12,14,19].
∗
Corresponding authors.
E-mail addresses: ajaykmishra1@yahoo.com (A.K. Mishra),
narenderkumar kaushik@yahoo.co.in (N.K. Kaushik).
1386-1425/$ – see front matter © 2007 Elsevier B.V. All rights reserved.
doi:10.1016/j.saa.2007.05.046

A.K. Mishra, N.K. Kaushik / Spectrochimica Acta Part A 69 (2008) 842–848
843
2.1.1. Preparation of N,N-diphenyl-N-thiohydrazide (L1)
In a three necked round bottle flask 8.46 g (0.05 mol) of
diphenylamine was dissolved in 40 mL methanol taken and
chilled it. To this, a chilled solution of 2.8 g (0.05 mol) potas-
sium hydroxide in 1 mL water and 10 mL methanol was mixed
with constant stirring. The mixed solution was treated with
an ice-cold solution of 3.02 mL (0.05 mol) carbon disulphide
(density 1.26) in 3 mL methanol. The temperature of the reac-
tion mixture was maintained below 10 ◦C by keeping flask
in a freezing mixture of common salt and ice. During the
process, a white crystalline precipitate of N,N-diphenyl dithio-
carbamate separated. It was filtered, washed with ice-cold
aqueous methanol. The product was then suspended in 10 mL
methanol and treated with freshly prepared potassium chloroac-
etate [(0.05 mol) {potassium chloroacetate was obtained by
dissolving 4.73 g chloroacetic acid in 3 mL ice-cold water and
mixing it in 5 mL aqueous solution of 2.8 g potassium hydrox-
ide}]. The temperature of the reaction mixture was kept at
about 40 ◦C for an hour and the contents were left overnight
at room temperature. After 24 h methanolic solution of 2.44 mL
(0.05 mol) hydrazine hydrate (density 1.026) was added to the
reaction mixture. The content was then heated on a water bath
for about 45 min when the desired product began to separate
out. It was cooled in ice for 24 h and filtered. N,N-Diphenyl-N-
CHNS-analysis; found (calculated)%: C 63.89 (64.19), H
5.33 (5.35), N 18.68 (17.28), S (12.67) 13.16; mass spectra
(CH3OH); m/z 243.59.
2.1.2. Preparation of
(N,N-diphenyl-N-thio)-1,3-propanediamine (L2)
14.15 g (0.05 mol) N,N-diphenyl dithiocarbamate prepared
as earlier was suspended in 25 mL methanol and treated
with freshly prepared potassium chloroacetate [(0.05 mol)
{potassium chloroacetate was obtained by dissolving 4.73 g
chloroacetic acid in 3 mL ice-cold water and mixing it in 5 mL
aqueous solution of 2.8 g potassium hydroxide}]. The temper-
ature of the reaction mixture was kept at about 40 ◦C for an
hour and the contents were left overnight at room temper-
ature. After 24 h methanolic solution of 4.36 mL (0.05 mol)
1,3-propanediamine (density 0.85) was added to the reaction
mixture. The content was then heated on a water bath for
about 45 min when the desired product began to separate out.
It was cooled in ice for 24 h and filtered. (N,N-Diphenyl-N-
thio)-1,3-propanediamine thus obtained was recrystallized from
methanol and dried under vacuum over CaCl2 at room temper-
ature.
The reactions taking place in the preparation are shown
below:
CHNS-analysis; found (calculated)%: C 68.23 (67.36), H 6.53
(6.67), N16.23 (14.70), S(10.61)11.20;massspectra(CH3OH);
m/z 285.71.
thiohydrazide thus obtained was recrystallized from methanol
and dried under vacuum over CaCl2 at room temperature.
The reactions taking place in the preparation are shown
below:

844
A.K. Mishra, N.K. Kaushik / Spectrochimica Acta Part A 69 (2008) 842–848
2.2. Preparation of complexes
following formula:
No. of conidia germinated in drug treated well
PSGI = 100 −
×100
2.2.1. Preparation of thiohydrazide and thiodiamine
[Ni(L)2Cl2] & [Ni(L)2(OCOCH3)2] complexes where
L = L1 and L2
No. of conidia germinated in control well
The corresponding ligand L [where L1 (0.122 g, 0.5 mmol),
L2 (0.143 g, 0.5 mmol)] in methanol and added with constant
stirring to few drops of 1N HCl solutions of corresponding metal
salt [Nickel chloride (0.059 g, 0.25 mmol) and Nickel acetate
(0.062 g, 0.25 mmol)]. The solution was stirred for 4–5 h. The
light green colour of nickel complex appeared immediately,
which separated, washed with ether and dried in desiccator over
CaCl2 under vacuum.
2.4. In vitro antibacterial activity
Most of the compounds have been screened in vitro against
Escherichia coli (E. coli) and Pseudomonas aeruginosa (P.
aeruginosa). Various methods [23–26] are available for the eval-
uation of the antibacterial activity of different types of drugs.
However, the most widely used method [26] consists in deter-
mining the antibacterial activity of the drug is to add it in known
concentrations to the cultures of the test organisms.
2.3. In vitro antifungal activity
2.4.1. Disc diffusion assay
The disc diffusion assay was used to determine antibacte-
rial activity of the drug using Gram positive and gram negative
strains of bacteria namely Escherichia coli (E. coli) and Pseu-
domonas aeruginosa (P. aeruginosa). Base plates were prepared
by pouring 10 mL of autoclaved Muller–Hinton agar (Biolab)
into sterile Petri dishes (9 cm) and allowing them to settle.
Molten autoclaved Muller–Hinton that had been kept at 48 ◦C
was inoculated with a broth culture (106 to 108 mL−1) of the test
organism and then poured over the base plate. The discs were
air dried and placed on the top of the agar layer. Four replicants
of each drug tested (four disc per plate) with a gentamycin disc
(0.5 ␮g/disc) as a reference. The plated were then incubated for
18 h at room temperature. Antibacterial activity is expressed as a
ratio of the inhibition zone produced by the drug to the inhibition
zone produced by the gentamycin standard.
Most of the compounds have been screened in vitro against
Aspergillus fumigatus, Aspergillus flavus and Aspergillus niger.
Among several methods [20] available, the one method [21,22]
that is common in use in recent times has been adopted.
2.3.1. Microbroth dilution assay
The susceptibility of the fungi to various fractions of com-
pounds was assayed by microbroth dilution method. Sabouraud
dextrose medium was dissolved in glass double distilled water
and autoclaved at 10 psi for 15 min. A volume of 90 ␮L
of medium was added to the wells of cell culture plates
(Nunc Nunclon). The different concentrations in the range of
1000–15 ␮g/mL of various fractions were prepared in duplicate
wells and then the wells were incubated with 10 ␮L of conidial
suspension containing 1 × 104 conidia. The plates were incu-
bated at 37 ◦C and examined macroscopically after 48 h for the
growth of Aspergillus mycelia. The activity was represented as
−ve if growth was there and +ve if medium appeared clear
without any visible growth of A. fumigatus, A. flavus and A.
niger.
2.4.2. Micro-dilution antibacterial assay
The serial dilution technique, using 96-well micro-plates to
determine the minimum inhibitory concentration (MIC) of the
drugs for antibacterial activity was used. Two milliliters cul-
tures of four bacterial strains of Escherichia coli (E. coli) and
Pseudomonas aeruginosa (P. aeruginosa) were prepared and
placed in a water bath overnight at 37 ◦C. The overnight cul-
tures were diluted with sterile Muller–Hinton broth. The drugs
were resuspended to a concentration of 60 ␮g/disc (in dmso)
with sterile distilled water in a 96-well micro-plate. A similar
twofold serial dilution of gentamycin (Sigma) was used as posi-
tive control against each bacterium. One hundred microliters of
each bacterial culture was added to each well. The plates were
covered and incubated overnight at 37 ◦C. To indicate bacterial
growth p-iodonitrotetrazolium violet was added to each well
and the plates incubated at 37 ◦C for 30 min. Bacterial growth
in the wells was indicated by a red colour, whereas clear wells
indicated inhibition.
2.3.2. Spore germination inhibition assay
The basic method for spore germination inhibition was mod-
ified and used to evaluate the activity of various test fractions
against fungi. The A. fumigatus, A. flavus and A. niger were
grown on Sabouraud dextrose agar plates and their homoge-
nous conidial suspension was prepared in the Sabouraud maltose
broth. The conidia were counted and their number in the sus-
pension was adjusted to 1 × 104 mL−1. Various concentrations
of the test samples in 90 ␮L of culture medium were prepared
in 96-well flat bottom micro-culture plates (Nunc Nunclon) by
double dilution method. The wells were prepared in duplicates
for each concentration. The wells were inoculated with 10 ␮L of
conidial suspension containing 100 5 conidia. The plates were
incubated at 37 ◦C for 10 h and then examined for spore germina-
tion under inverted microscope (Nikon Diphot). The number of
germinated and non-germinated conidia was recorded. The per-
cent spore germination inhibition (PSGI) was calculated using
3. Result and discussion
3.1. Elemental analysis
Elemental analysis (Table 1) reveals the purity of the com-
plexes. All complexes are soluble in acetone, DMF, etc. The

A.K. Mishra, N.K. Kaushik / Spectrochimica Acta Part A 69 (2008) 842–848
845
Table 1
Elemental analysis of the complexes
Complexes
Found (calculated) (%)
C
H
N
S
Cl
Metal
Ni(L1)2Cl2
50.45 (50.65)
54.18 (54.29)
55.10 (54.86)
57.47 (57.83)
4.23 (4.22)
4.77 (4.83)
5.36 (5.43)
5.80 (5.89)
13.89 (13.64)
12.74 (12.67)
11.79 (12.00)
11.56 (11.24)
10.96 (10.39)
9.55 (9.65)
9.29 (9.14)
8.86 (8.57)
11.12 (11.53)
–
10.86 (10.14)
–
9.85 (9.58)
8.95 (8.89)
8.50 (8.43)
8.06 (7.89)
Ni(L1)2(OCOCH3)2
Ni(L2)2Cl2
Ni(L2)2(OCOCH3)2
molar conductance values of the isolated complexes measured
in DMSO are found to be less than 12 ohm−1 cm2 mol−1 sug-
gesting their non-electrolytic nature.
nitrogen vibration, ν(M–N) are assigned to the new bands [30]
in the far IR between 470 and 490 cm−1, while in the region
between 370 and 390 cm−1 gives metal–sulphur, ν(M–S) band
stretching [31]. The band at ∼280–300 cm−1 is assigned due to
ν(Ni–Cl) stretching vibrations.
3.2. Electronic spectra
The electronic spectra (Table 2) of the ligands exhibits bands
3.4. NMR spectra
*
at ∼280 nm is observed which is assigned to a ␲–␲ electronic
1H NMR spectra of ligands and complexes were recorded in
deuterated acetone taking TMS as internal standards:
transition. The electronic spectrum of the nickel(II) complex
show d–d bands at ∼640 nm. These bands can safely be assigned
3
3
to the 3A2g → T2g and 3A2g → T1g(F) transition, respectively,
of six coordinate nickel(II). In addition to showing the intra-
ligand and d–d bands, the complex also exhibits a strong band
at ∼480 nm, which can safely be assigned to ligand to metal
charge-transfer transition [27,28].
• δ (ppm): 7.16–6.57 (m, 10H, Ar–H), 9.09 (br s, 1Ha, –NH),
3.26 (br s, 2Hb, –NH2).
• [Ni(L1)2Cl2] δ (ppm): 8.21–7.29 (m, 20H, Ar–H), 9.16 (br s,
2Ha, –NH), 4.19 (br s, 4Hb, –NH2).
• [Ni(L1)2(OCOCH3)2] δ (ppm): 8.18–7.06 (m, 20H, Ar–H),
9.16 (br s, 2Ha, –NH), 4.02 (br s, 4Hb, –NH2).
• δ(ppm):7.19–6.46(m, 10H, Ar–H), 8.92(brs, 1Ha, –NH), 2.9
(t, 4Hb, –CH2), 1.47 (m, 2Hc, –CH2), 3.8 (br s, 2Hd, –NH2).
• [Ni(L2)2Cl2] δ (ppm): 8.11–7.36 (m, 20H, Ar–H), 9.02 (br s,
2Ha, –NH), 2.97 (t, 8Hb, –CH2), 1.79 (m, 4Hc, –CH2), 4.21
(br s, 4Hd, –NH2).
3.3. IR spectra
In the IR spectra (Table 3), Strong bands at 2920–3250 cm−1
in thiodiamines are assigned due to –NH stretching vibrations
of NH2 and NH groups. The NH stretching of ligand has been
found to shift to higher frequencies, the change being associated
with coordination of terminal NH2 nitrogen to the metal ion.
Band located at ∼1600 cm−1 is assigned to NH2 deformation
vibration. A sharp and strong band at ∼890 cm−1 in IR spectra
of free ligands which is shifted in complexes is attributed due
to ν(C S) [14,29]. In the far of the Ni(II) complexes, the metal
• [Ni(L2)2(OCOCH3)2] δ (ppm): 8.49–7.42 (m, 20H, Ar–H),
8.96 (br s, 2Ha, –NH), 3.08 (t, 8Hb, –CH2), 1.67 (m, 4Hc,
–CH2), 4.17 (br s, 4Hd, –NH2).
The 1H NMR spectrum of thiodiamines [32–34] shows sig-
nals at δ ∼ 9.0 and δ ∼ 4.0 ppm, due to the presence of NH
protons which are lost on D2O exchange. This is observable
in the complexes also suggesting that hydrogen bonding to the
solvent occurs in the complexes as well as free ligands. Two
signals at δ ∼ 2.5 and δ ∼ 1.5 ppm, which show the presence of
different –CH2 group in the complex.
Table 2
Electronic spectra of the complexes
Complexes
Ni(L1)2Cl2
λmax (nm)
log (ε)
300
365
420
610
3.93
3.18
2.74
2.24
3.5. In vitro antifungal study
293
387
426
614
3.88
3.41
2.94
2.49
In the current study (Table 4) of some synthesized complexes
were tested against pathogenic fungal strains such as A. fumiga-
Ni(L1)2(OCOCH3)2
278
338
410
617
4.12
3.78
3.44
2.98
Table 3
Ni(L2)2Cl2
Electronic spectra of the complexes
Compounds
νN–N
νC
νM–N
νM–S
νM–Cl
S
278
358
416
623
4.18
3.78
2.96
2.89
Ni(L1)2Cl2
1022
1022
1033
1024
805
818
865
854
484
474
466
468
365
375
390
381
310
299
295
285
Ni(L1)2(OCOCH3)2
Ni(L2)2Cl2
Ni(L2)2(OCOCH3)2
Ni(L2)2(OCOCH3)2

846
A.K. Mishra, N.K. Kaushik / Spectrochimica Acta Part A 69 (2008) 842–848
Table 4
In vitro antifungal studies of the complexes
S. No.
Complexes
A. fumigatus
A. flavus
A. niger
MDA (␮g/mL)
PSGI (␮g/mL)
MDA (␮g/mL)
PSGI (␮g/mL)
MDA (␮g/mL)
PSGI (␮g/mL)
1
2
3
4
Ni(L1)2(OCOCH3)2
Ni(L1)2Cl2
Ni(L2)2(OCOCH3)2
Ni(L2)2Cl2
62.5
125
250
62.5
125
250
62.5
125
250
62.5
125
250
125
250
500
125
250
500
500
500
500
500
1000
1000
Amphotericin B
5
5
5
5
5
5
Where, MDA: Micro-dilution activity and PSGI: percent spore germination inhibition.
tus, A. flavus and A. niger. Amphotericin B was used as reference
drug for fungi. The minimum inhibitory concentrations (MICs)
by microbroth dilution assays (MDA) and percent spore ger-
mination inhibition assays (PSGIA) is 62.5–500 ␮g/mL. The
complex [Ni(L2)2(OCOCH3)2] and [Ni(L2)2Cl2] had highest in
vitro antifungal activity against pathogenic fungal strains. The
reason for the highest activity might be related to the pres-
ence of acetate group and 1,3-propanediamine group in the
[Ni(L2)2(OCOCH3)2] complex. The other complex show mod-
erate activity may be due to the fact that Aspergillii have hard
chitinousouterwallandtherefore, higherconcentrationoffungi-
cidal compounds may be often required to kill the fungi.
showed significant antibacterial activity and the bacterial strains
with the zone of inhibition, 8 mm at minimum inhibitory con-
centration (MIC) of 60.0 ␮g/disc.
3.7. Thermal studies of the complexes
The thermogravimetry (TG) and differential thermal analy-
sis (DTA) study in air atmosphere has been carried out for one
3.6. In vitro antibacterial study
In the antibacterial study (Table 5) of some synthesized com-
plexes was tested against pathogenic bacterial strains such as
Escherichia coli (E. coli) and Pseudomonas aeruginosa (P.
aeruginosa) using the disc diffusion method. Gentamycin was
used as reference drug for bacteria. In general, the compounds
Fig. 2. The curve plotted by Coats-Redfern method for [Ni(L1)2(OCOCH3)2]
for step II.
Table 5
In vitro antibacterial studies of the complexes
S. No.
Complexes
Zone of inhibition (mm)
Table 6
Kinetic parameters from TG for [Ni(L1)2(OCOCH3)2] complex by Coats-
Redfern method (step I)
E. coli
P. aeruginosa
1
2
Ni(L2)2(OCOCH3)2
Ni(L2)2Cl2
8
–
8
8
ꢀ
ꢁ
−ln(1−α)
α
1 − α
T (K)
T2
1/T ×10−3
−log
2
T
Gentamycin
16.0
16.0
0.04
0.33
0.51
0.77
0.95
0.96
0.67
0.49
0.23
0.05
318
362
398
434
458
101,124 3.14
131,044 2.76
158,404 2.51
188,356 2.30
209,764 2.18
6.76
5.88
5.71
5.47
5.21
Table 7
Kinetic parameters from TG for [Ni(L1)2(OCOCH3)2] complex by Coats-
Redfern method (step II)
ꢀ
ꢁ
−ln(1−α)
α
1 − α
T (K)
T2
1/T ×10−3
−log
2
T
0.29
0.44
0.79
0.92
0.95
0.71
0.56
0.21
0.08
0.05
508
546
658
691
708
258,064 1.97
298,116 1.83
432,964 1.52
477,481 1.45
501,264 1.41
6.24
6.07
5.8
5.64
5.58
Fig. 1. The curve plotted by Coats-Redfern method for [Ni(L1)2(OCOCH3)2]
for step I.

A.K. Mishra, N.K. Kaushik / Spectrochimica Acta Part A 69 (2008) 842–848
847
Table 8
Thermal data of the thiohydrazide
Complexes
Step No.
TG (Coats-Redfern method)
ꢀH (kJ g−1
)
Temperature range (K)
n
Ea (kJ mol−1
)
S# (J K−1 mol−1
)
I
II
301–469
469–714
1
1
28.62
21.49
8.55
6.18
42.45
106.12
[Ni(L1)2(OCOCH3)2]
complex. Thermal studies were utilized to elucidate the num-
ber of kinetic and thermodynamic parameters. From TG curve,
order of reaction (n), activation energy (Ea), apparent activa-
tion entropy (S#) were enumerated by the Coats-Redfern method
[35]. From the DTA curves, the heat of reaction was calculated.
Kinetic parameters of each step from Coats-Redfern method
were shown in Figs. 1 and 2 and the thermal data were tabulated
in Tables 6–8.
The DTA profile (Fig. 4) shows one endotherm at 338 K
and one endotherm at 445 K correspond to the fusion of the
compounds and one exotherm at 578 K corresponding to the
oxidation of organic moieties.
4. Conclusion
The electronic spectra of the complexes suggest that all the
complexes are found to be diamagnetic. The spectral studies
indicate that, the complexation takes place to the metal ion
is through azomethine nitrogen and thioamide sulphur. The
in vitro antifungal activity of complexes as compared with
standard drug Amphotericin B shows significant activity. The
minimum inhibitory concentrations (MICs) by microbroth dilu-
tion assays (MDA) and percent spore germination inhibition
assays (PSGIA) is found to be 62.5–500.0 ␮g/mL. The in vitro
antibacterial study of the complexes as compared with stan-
dard drug Gentamycin shows significant activity. The bacterial
strains with the zone of inhibition were observed, 8 mm. The
thermal data (TG/DTA) of the complex indicates the reaction
orders are found to be one and activation energy, apparent acti-
vation entropy and heat of reaction are found to be significant.
It is worth to mention that trials to get crystal suitable for X-ray
structure determination went in vain due to amorphous character
of the complexes.
3.7.1. [Ni(L1)2(OCOCH3)2] complex
TG curve (Fig. 3) shows two-step decomposition. The first
decomposition step (301 K–469 K) corresponds to the loss of
all organic moieties for which observed and calculated weight
losses are 73.42% and 73.30%, respectively. The second step
starts at (469–714 K) corresponds to the formation of nickel
sulphide for which the observed and calculated weight losses
are 85.0% and 86.27%.
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