Carbonyl releasing Schiff base complex of Fe (III): synthesis, physicochemical characterization, antimicrobial and anticancer studies

Article abstract of DOI:10.1007/s12039-020-1746-y

Abstract: The carbonyl releasing Schiff base chelate derived Fe(III) complex has been synthesized following the simple wet chemical method. The rhombohedral packing of ligands with the metal ion in the complex was confirmed by its XRD pattern and FTIR spe

Full text of DOI:10.1007/s12039-020-1746-y

J. Chem. Sci. (2 0 2 0 ) 13 2: 44
Ó In di an Aca dem y of Sc i en c es
h t tp s: / / d o i .o r g /1 0 . 1 0 07 /s 1 20 39 - 02 0- 17 46 - y Sadhan
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REGULAR ARTICLE
Carbonyl releasing Schiff base complex of Fe (III): synthesis,
physicochemical characterization, antimicrobial and anticancer
studies
*
R V KUPW ADE an d V J SAW A NT
De p ar t m en t of Ch e m is t ry , S m t . K as tur bai Wa lch an d C ol l ege , S angl i , Mah a ras h tr a 416 4 16, In di a
E- ma i l: v1 11 31 @r e di f fm a il.c om
MS r ecei v ed 2 0 A u gu s t 2 01 9 ; r ev i s ed 1 4 O ct o b er 2 0 1 9; accep t ed 1 5 O ct o b er 2 0 1 9
Abstract. Th e ca rb on y l r ele as in g S chi f f bas e che lat e der iv ed F e(I II ) com pl ex has bee n s ynt hes i z ed f ol -
l o wi n g th e s im p le w et ch em ic al m et hod . The rh om bohe dr al pac kin g of l ig ands wi t h t he m et al i on i n t he
c o mp l e x w as co nfi r me d by it s X RD pat t er n and F TIR s pec tr u m . C om pou nds wer e cha r act eri ze d by U V-V i s. ,
PL , F TI R , X RD an d TEM te chn iq ue s . B et t er bi oco m p at i bil i t y of t he com p lex t han t hat of t he pur e S ch if f b as e
h a d be en el abo r a te d on gr am - p os i ti ve and gr am -n ega ti ve bac ter ia by Ag a r wel l di s c-d i ff us i on ant i b ac t er i a l
s cr ee n i ng . Th e co m pl e x al s o di s pl ay ed pH -res pon s iv e in vitro ant i ca nce r t hera py on MC F -7 br eas t c an ce r
c el l s a s r eve ale d by MT T as s a y. Th e rel ea s e of C O and S chi ff bas e as wel l as t he i nt eract i on o f F e(I II ) wi t h
t h e m i to ch on dr ia in s id e th e ce l l ar e t he key fac to r s of cel l bi oc om pa ti bi l it y. Thi s C OR M com p le x h ad
e x hi b i t ed hi gh e r an ti ca nc er ac tiv it y o n MC F -7 cel l s t han t he S chi f f bas e and t hus pot e nt i al can did at e f or t he
fu t u re bi om ed ic al ap pl ica ti on s .
Keywords. Ca rb on y l r ele as in g; S chi ff bas e ; che l at e; ant i ca nce r.
1
. Introduction
W he n suc h li ga nds c om bine to ge the r in a c he l at e of
bi oa ct ive m et al s li ke F e( I I I ), th es e c om ple xes pla y
si gnifi c a nt r ole s in bi o si gna lli ng in side c el ls a nd give
e ff e c ts of bi oc om pa tib ili ty or c yto toxi c ity . H enc e ,
S ch if f ba se c om ple xe s a lon g wit h c ar bo nyl liga nd s
r es ult in f as t e ndoc yt osi s a nd r el e as e of li ga nds ins ide
c el ls to e ff e c t in to R OS pr od uct ion a t pH gr a di e nt of
c el ls. Thi s R OS pr od uce d in to c el ls le a ds to a ntim i-
c ro bia l, a nti ca nc e r or c yto toxi c a nd bi oc om pa tibl e
e ff e c ts on c el ls. P ar a ll el e ff e c ts of bi oc om pa tibi lity
ha ve be e n sho wn by a nti bio tic li ga nd c om ple xe s w ith
C a r b o n y l re le a s i ng co mp le xe s an d mo le c ule s
(C O RM ) a re g a in in g mo re i nt er es t du e t o t h ei r ve r -
s a t i le p ro p e rti e s i n bi o med i cal fie ld s, su ch as a nti mi -
c ro b ia l , a n ti c a n c e r, an t io xi d an t an d an t i- pr o li f er a ti ve
1
a g e n ts . Al ik e th e NO, ca rb on yl ( CO) l ig an d is a lso
c el l s ig n a ll in g s pe ci es wh ic h ex hi b it s va so d ila to r y,
2
a n t i -in fl a mm a to r y an d an t i- pr o li fe r at i ve ac t ivi tie s.
C a r b o n y l
re le a s in g
sp ec ie s
ar e
g en er a ll y
s u p ra m o lec u l a r c om pl ex ag en t s wh ic h pa ss th ro ugh
t h e c e ll b a rri ers . W he n t he ir up t ak e t ak es pl ac e by
l y s os o m e s in c e lls at ac i di c p H, t he r el ea se of C O
m o l e c u le ta k e s pl a ce an d ROS ( Rea ct iv e Oxy gen
Sp e c ie s ) g e t g e n er at ed by ce l l pr o to n ef flu x. He nc e,
s u c h c o mp le x e s a c t as an an t im ic ro bi a l an d an t ic a nc er
a g e n t wi th b e tt e r b io co mp at i bi li ty . Sc hi f f b as es a re
g e n e ra lly c h e la tin g l ig an ds co nt a in in g car bi mi de
b o n d s fo rm e d a ft er r eflu xi n g al d eh yd es wi th a mi ne s
i n s y n th e ti c p ro to co ls . Th es e l ig an ds ar e t h e be st
a n t i mic ro b i a l a g e n t s an d f or m be t te r co mp le xe s wit h
a v ari e ty o f tr an s it i on an d i nn er t ra ns it i on me ta ls wit h
g o o d b io c o mp a t ib i li ty .
3
spe c ia l bi oc om pa tib le m et al s. R OS- ba se d a nt imic r o-
bi al a ct ivi ty of P d( I I) c om ple x ha s be e n r ep or ted by W
4
Gue r r a et al. R ec e nt wor k on he te r oc yc li c a nd S c hif f
ba se li ga nd c om ple xe s ha ve be e n no t onl y r ep or t ed the
a nti mi cr ob ia l pr op er ti es bu t a lso DNA cl ea va ge
a ct ivi tie s in c el ls le a din g to th e pr od uct ion of R OS in
5– 7
c el ls a nd bi ome di c al in te rf a c e m ec ha ni sm s. S imi la r
r es ea r c h of he te r oc yc li c a nd c ar bi mi de c on ta ining
S ch if f ba se ty pe li ga nds a nd th ei r m et al c om ple xe s
ha ve be e n r ep or te d f or th ei r bi ome di c al app lic a -
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c yc lic spe c ie s a nd S ch if f ba se s a lon g wit h the ir
c om ple xe s wit h tr a nsi tio n m et al s, th es e c om ple xe s
ha ve e xhi bit ed th e sup r am ole c ula r na tu re to pas s f r om
*
F o r co rr e sp on den ce

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Pa g e 2 o f 1 2
J. Chem. Sci. (2 020) 1 32: 44
c el l me m b ra n e s ea si l y an d p ro du ce ef f ect s of bi o- 2.3 Wet chemical synthesis of CORM, carbonyl -
c o mp at ib i li t y a n d DNA i nt er ac t io ns t o r eal i ze pot e n- Schiff base complex of Fe(III)
1
3 –1 7
t i al e ffe c ts o n c e ll di v is i on s an d p ro li f er at io ns.
The car bony l -co nt ain i ng S chi f f bas e m et al com pl e x o f
F e(I II) was s ynt h es i zed by bub bl i ng C O i nt o t he fla sk
con tai n i ng S chi f f bas e and F e(I II) ni t rat e pr ec ur s or u si n g a
wet che m i cal m et hod (S ch em e 1 ). In det ai l , t he S ch if f b as e
wi t h F e(I II) i n 2: 1 m M pr opor t io n i n t he et han ol - wat e r
s ol vent s ys t em wer e refl u xe d i n R . B . fl as k fo r 3 h a nd t he
pr ecurs o r was t hen add ed i n t he fl as k wi t h dou bl e d is t i l le d
wat er . Th e gas e ous C O l ig and was pr oduc ed i n se p ar a te
fl as k by t he rea ct ion of con c. HC l wi t h cal ci um ca rb o na t e
I n c o n ti n u a ti o n of t he se i de as, we h ad sy nt he siz e d
n e w c a rb o n y l re le a si ng Sc hi f f ba se co mp le x o f F e( I I I ).
In a d d it io n to p h ys i co che mica l ch ar ac te ri z at i on of th e
s i m p le S c h iff b a se an d i ts ca rb on yl co mp le x wit h
Fe ( III), th e a n ti m ic ro bial b io co mp at i bi l i t y an d a nti -
c an c e r p o te n tia ls h ave b een t es te d by in vitro a ssa y.
Th e h ig h e r a n ti m ic ro bi a l an d an t ic an ce r po t e nti al of
t h e c o mp le x a s co mp ar ed t o Sc hi f f ba se ha s be e n
e l ab o ra te d o n s pe ci al M CF- 7 hu ma n b rea st c an ce r and zi nc pow d er m i xt ure. Th en t he C O l ig ands p ro d uc e d
c el l s b y in vitro M TT as sa y. Co mpl e x ex hi bit ed s epa rat el y i n ano th er fl as k was pas s e d and bub bl ed in l i ga n d
i n c r e as e d e n d o c y t osi s i ns id e n ega t iv el y ch ar g ed c el l and m et al pr ecurs o r m i xt u re t o get car bo nyl re l ea si n g
C OR M com p le x of F e(I II ) con t ai ni ng C O l ig an ds a nd
m e m b ra n e s o f b a ct er i a an d ca nc er ce l ls an d pr od uce d
S chi ff bas e . Th e com p le x fo rm ed t hus was was he d wi t h
h i g he r a mo u n t o f ROS at ac i di c p H t ha n Sc hif f ba se ,
et hano l -w at er s ol vent s ys t em and dr ied i n t he ove n.
C O , im p ly i n g th e ef f ect o f Fe (I I I) sp ec ie s to war ds
i n t ri n s ic a p o p to s is o f ca nc er ce l ls .
18 –20
Th us , c ar bo nyl
re l ea s i n g S c h iff b ase co mp le x o f Fe (I I I) ca n be c on-
s i d er ed a s a p o te n ti a l ca nd i dat e f or f ut ur e bi o me di c al
a p p li c a tio n s .
2.4 Structural and morphological
characterization of CORM-Fe(III) complex
The s t ruct ur e, m or phol ogy , par ti c l e di am et er rang e a nd
t ypes of bon di ng of fu nct i onal i ti es i n t he C OR M c om p le x
of F e(I II) was det er m i ned bas e d on phy s i coc hem i ca l c ha r-
act eri za t io n us i ng UV -Vi s . , P L, F TIR , XR D s pec t r om et r y
2
. Experimental
2
. 1 Materials and cell cultures
OH
Al l t h e c h em i ca l s u s ed f or th e s yn th es is of S chi f f b as e and
i ts c ar bo n y l c o mp l e x w ith F e( I I I) an d th ei r in vitro bi o-
l o gi ca l s cr e e n in g s uc h as F er ri c ni tr at e, P -n it r o ani l i ne,
Be nz al d e hy d e , Zi n c po w d er , Ca lci um ca rb on at e, C onc.
HC l , Et h a no l we re of A . R. gr ad e . Th es e ch em ic al s wer e
p u rc h a se d fr o m S. D . F in e Ch em . Ltd . an d Me rc k Lt d. and
we re u s ed wi t h o u t f ur th er pu r ifi cat io n. Th e ce ll cul t ur e
m edi u m s u ch a s a ga r gr o wth br o t h an d ba ct eri al cul t ur e,
f et al b o v i n e s er u m, tr y ps i n bu f fe r w er e ob ta in e d fr om
Hi m ed i a Lt d . a n d N CC S ce ll r epo s it o r y ce nt er , P u ne, In di a.
Th e h u m a n b re a st ca nce r ce l ls MC F- 7 w er e pu r ch as ed fr om
t h is c el l re p o s i t o ry . Th e do ub le -d i s ti ll ed w ate r w as obt a i ned
f ro m M i ll i p o re s y st em an d u s ed th r ou gho u t th e sy nt hes i s
an d in vitro b i o l o gi ca l s cr ee nin g te s ts .
+
H
2
N
NO
2
CHO
Salicyladehyde
P-nitro aniline
-
H O 3h reflux in ethanol
2
OH
CH
Schiff base ligand
N
NO
2
CO bubbling
Fe(NO ) stirred with ligand
3 3
NO2
2
. 2 Synthesis of Schiff base ligand
CO
O
Th e s i mp l e Sc h i f f b as e li ga nd w as s yn t he s ize d by refl u xin g
P - ni tr o a ni l l i n e a n d Be nz al deh yd e at 25 0 °C on th e con s t ant
fl am e i n R .B . fla s k w ith co nd en s er f or 3 h. Th e yel l ow
p r od u c t fo r me d w ate r- w as h ed w ith et han ol to rem o ve
u n re ac t e d o rg a n i c pr ec ur s o r s an d dr i ed in th e ov en bel ow
N
(
NO )
3 3
Fe
N
O
CO
NO2
8
0 °C . Th e Sc h i f f b as e po w d er th en s ub je cte d to phy s ico -
ch em i c a l t h e c o m p l ex us i n g U V- V is . , P L, F IT R s pec tr o m -
et r y . Th e fo r ma t i o n of th e pr o du ct w as co nfi r m ed o n t he
b as is o f p h y s i ca l co ns t ant an d TLC ( s ee pr o toco l i n
S ch e m e 1 ).
CORM Fe (III) Schiff base complex
Scheme 1. S y nt hes i s pr ot ocol of S chi ff bas e l iga n d a nd
car bon yl -s ch if f bas e F e(I II ) com pl ex.

J. Chem. Sci. (2 0 2 0 ) 13 2: 44
P
a
g
e
3
o
f
1
2
4
4
t ech n i q u e s a n d TEM m ic ro s cop i c an al ys i s . Th e s pec tr o ni cs C el ls wi t hou t t reat m e nt wer e con s i der ed as a con tr ol a s we l l
d o u b l e b e am UV -V is . s pe ctr om e te r w ith w ate r as bla nk was t o eva lu ate i ts cyt ot ox ici t y. C e l ls wer e fu rt her i ncuba t e d f or
u s ed t o d e te rm i n e th e ab s or pt ion s pe ctr u m of co m pl e x t o 48 hou rs , and rel at i ve ant i ca nce r act i vi ty was as s e s se d wi t h
co mp a re wi t h Sc h i ff ba s e. To co nfi r m f un cti on al i ti e s pr e- MTT as s a ys . Af te r 48 h, MTT as s a y was car ri e d o ut . I n
s en t i n c o mp l e x a n d a w ith S chi f f ba s e, P er ki n Elm er s eri es br ief , MTT s ol ut i ons (2 0 lL of 5 m g/ m L ) wer e adde d a ft e r
F TI R s p ec t ro m et e r w as us e d w ith K Br pe ll et te c hn iqu e. The t reat m e nt and cel l cul t ure wer e aga in i ncu bat ed f or a n
P L e mi s s i o n s p ec t r um of co m pl e x an d S c hi f f bas e wer e add it i o nal 4 h. Di m et hy l s ul p hox id e (1 50 lL s ol ut i on ) wa s
d et erm i n ed u s i n g J as co ty pe s pe ct r ofl uo ro m et er w it h exc i- add ed t o each wel l t o s ol u bi l iz e t he b l ue fo rm azan c ry st a l s,
t ati o n i d en t i t y o f c o m pl ex an d S chi f f ba s e in et han ol s ol v ent and opt i cal den s it y at 492 nm was rec o rd ed fo r c ul t u r e
wi t h t h e s am e p p m . Co nc ent r ati on s . Th e X -r ay di ff ract i on m edi um . C el l vi ab i li t y (% ) fo r exp os u re of S chi ff b as e a nd
p at te rn o f t h e c o mp le x w as de te rm in ed us i n g X -r ay s pec - com p le x d os es wer e cal cul at ed as fo ll ows ,
t ro m e t er b y p o wd er di f fr ac t io n te chn iq ue to el abo ra t e t he
Optical density at 4 9 2 nm in test cells
p ack i n g o f l i g an d s wit h m et al in co m pl e x, hy br id i zat i on and
%
Cell viability ¼
Optical density at 492 nm in control cells
 100
cr y s t al s y s t e m o f c om p le x. Th e pa rt ic le r ang e of co m pl ex t o
p as s c el l t h ro u g h m em b r an es w as de te rm in ed us i n g TEM
m icr o s co p i c a n al y s i s an d S AED pa tt er ns w er e m at ch e d wi t h
XR D d a ta t o c o nfi rm th e po w der cr ys ta l s ys t em of com pl ex.
Th e ant i ca nce r act i vi ti es of S c hi ff bas e and c om p le x
dos e s wer e el abor a t ed i n t er m s o f cel l vi abi l it y and p lo t t ed
as a fu nct io n of con ce nt rat i ons t o com par e t he e ff ec t s.
F i nal l y, t hes e cul t ur es wer e s ubj ect ed t o DA PI s t ai n i ng t o
el abor a t e i nt erna li za t io n of t he com pl ex i nt o can ce r c el l s,
and det er m in e t he m ech ani s m of cel l dea th s or apo pt o si s b y
i nt eract i ons fr om t he com pl ex by t he pr oduc t io n of i nt e r -
ani on s / i nt er-c ati ons or rel ea s e of l ig ands and me t al i on
i ns i de cel l fl ui ds .
2
. 5 Antimicrobial screening on gram-positive
and gram-negative bacteria by agar well disc
diffusion method
Th e c el l -p a rt i c le i n te ra ct io ns of m at er ia ls an d com pl exes
d emo n s t ra ti n g t h ei r r eac tiv i ty an d bi oc om p ati bi li ty can be
el ab o ra t ed u s i n g s i mp le in vitro an ti bac te ri al s cr eeni ng i n
b u ffe r s o l u ti o n s t o m ai nta i n ph ys i ol o gi ca l m im i cki ng pH at
m ate ri a l c el l i n t er a ct io ns . A s ce ll pH af f ec ts th e bi oc om -
p at ib i l i t y o f m o l ec u le s . H er e in th is w or k 15 , 20 and
2.7 DAPI staining and imaging of cancer cells
after MTT assay
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Af te r t he i ncub ati on wi t h S chi ff b as e/ com p l ex d o se s a nd
fu rt her MTT i nt era ct i ons , t he cel l s wer e was h ed wi t h PB S
we re d o s ed o n b a ct er ia l ce ll cu lt ur es gr o wn in ag ar br ot h on
d i scs , i n s id e t h e wel ls bo r ed on pl at es . Th e gr am -p os i t iv e
b act e ria Staph. Aurues, an d g r am - neg at iv e ba ct eri a E. Coli,
Kleb. we re g ro w n on cu lt ur e pl at es an d in hi bi te d by dos i ng
o f Sc h i ff b a se a n d co m p le x s ol u ti on s in b uf f er di s per s i ons
wi t h p h y s i o lo g i c al pH = 7. 4 by us e of ph os p ha te bu ff er. The
cu l t u r e p l at e s we r e in cu ba ted an d zo ne s of in hi bi tio n wer e
m ea su r e d , a n d b i o c om p ati bi li ty /an t im i cr ob ial pr o pe rt y of
S chi f f b a se a n d c o m pl ex w er e co m pa re d.
(
p hos pha te buf f er s al i ne) s ol u t io n and fi xed wi t h 4 %
par afor m al deh yde fo r 30 m i n, t hen cel l s wer e add ed wi t h
0 lL of DA PI and wer e i ncu bat ed fo r 20 m i n; fi n all y , a ft e r
2
s pr eadi ng o n s l id es , t he cel l wer e exa m in ed und er a flu o -
res c ent m i cro s cop e. The i nt ern al i zat ion of com p le x h ig h er
t han S chi ff bas e was exa m in ed b y t he s t a i ni ng and me c h-
ani s m of ant i canc er eff ect s and bi oco m p at i bil i t y / cy t ot o xi -
ci t y was dem ons t r ated .
2 . 6 In vitro MTT cell line anticancer assay
on MCF-7 human breast cancer cells
3. Results and Discussion
3.1 Morphological and structural characterization
of Schiff base ligand and the CORM Fe(III) complex
Th e a n ti c a n c er p o t e nt ia l of S chi f f ba s e an d co m p lex wer e
es t im a t e d a n d c o m pa re d on th e ba s is on in vitro MTT,
M C F-7 c e ll l i n e s p ec tr o m et ri c as s ay . Cy to t ox ic ity o f S chi ff
b as e a n d C OR M co m pl ex w er e el a bo r ate d in to MC F -7
3.1 a UV-Vis. absorption and PL emission
spectrum: UV- Vis. a nd P L spe c tr um of
S ch if f /c om ple x we r e de te r mi ne d to st ud y the
st ru ct ur al c ha ra c te r ist ic s, m et al to li ga nd c ha r ge
tr a nsf e r tr a nsi tio ns, bon din g wit hin th e m ole c ule a nd
(
Hu ma n B re as t c an ce r ce lls ) w ith MT T as s a ys . Cel l s (1 9
3
0 /m L) we re s ee d e d in 96 - wel l pl at es an d th en in cu bat ed
1
f o r 2 4 h a t 3 7 °C a nd 5 % CO at m os ph er e in an inc u bat or
2
wi t h 1 0 0 lL o f DME M m ed iu m s up pl em e nte d w it h 10%
f et al b o v i n e s er u m ( FB S) as a gr o wth m ed iu m and 1% a bsor pt ion /e mi ssion pr op er ty . He r e UV- Vis , the
p en i ci l l i n -s t re p t o m y cin s ol ut i on pe r w ell . Th is m edi um was a bsor pt ion spe c tr um of th e c om ple x ( Fi gur e 1)
t h en re p l ac e d wi t h 20 0 lL of th e P BS , ph os p ha te buf fer e xpl ai ns th e c ha rg e tr a nsf e r tr a nsi tio n of F e ( II I )
s al in e (p H =7 .4 ) m ed iu m co nt ain in g ei th er S chi f f bas e s or
co mp l e x d o s es (c o n ce nt r ati on 5, 10 , 15 , 20 an d 25 lg/ m L).
m et al io n wit h S ch if f ba se a nd c ar bo nyl li ga nd , to
e la bor a te th e bo ndin g in te ra c ti ons in th e c om ple x. The

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5
4
3
2
1
0
U V -V IS a b s o rp tio n s p e c tra o f s c h iff b a s e c o m p le x
5
d
F e (III) M L C T w ith C O
a n d c a rb im id e
2
0 0
3 0 0
4 0 0
5 0 0
6 0 0
7 0 0
8 0 0
W a v e le n g th n m
Figure 1. U V- V i s ib le ab s or pt io n s pec tr u m of C OR M S chi f f bas e com pl ex of F e(I II) .
s p e c tru m e x h ib its t he d if fu se d br o ad ab so rp t ion pe a ks li ga nd wit h F e( I I I ) io n in th e c om ple x. S o th e s pe ct r a
a t 2 3 5 n m a n d 3 5 5 nm f or t he M LCT t ra ns it i o ns f r om sup por t f or C O r el e as ing na tu re of th e c om pl ex , a s
Fe ( III) d e le c tr o n s t o CO an d ca rb i mi de b ond o f S ch if f S ch if f ba se is fi rm ly li nke d by c oor di na te bo nds a nd
b a s e li g a n d re s p ec ti v el y ( met al t o l ig an d c ha rg e C O e le ct r ons a re r ep r ese nt ing di ff e r en t a bs or ption
t ra ns f e r ta k e p la c e pr o bab l y du e t o no n b ond ed a nd m ax im a in UV- Vis spe c tr um of th e c om pl ex a t
Pi e le c tr o n s o f S ch if f ba se an d CO l ig an ds a nd d 235 nm r ep r ese nt ing m or e non - bond ing f r ee e l ec tr on s
e l ec tr o n s o f F e (II I) i n t he co mp le x) . Th e Sc h if f ba se ove r it . Thi s e la bor a te d th e f r ee si te of C O li ga nds f or
s h o ws h ig h e r O. D. f or a si n gl e pe ak n ear a t sa m e e as y r el e as e f r om c om ple x to be ha ve a s C OR M
a b s o rp ti o n wa v e le ng t h o f t he co mp le x at 36 5 nm . ( Not c om ple x f or be tt er c el l bi oc om pa tib ili ty . Ta ble 1
s h o wn ), b u t d a mp e ni ng an d pe ak sh i ft i ng t ake pl ac e sup por ts f or ML CT tr a nsi tio n id en tit ie s in S ch if f ba s e
fo r a b s o rp ti o n ma x im a of Sc hi f f ba se af t er b ond ing a nd C ORM c om ple x de te r mi ne d f r om UV- Vis a nd P L
i n t e ra c tio n o f c a rb i mi de bo n d wi th Fe (I I I) i ons in th e spe c tr um .
c o mp le x . He n c e , UV- Vis sp ec tr u m o f com pl ex
The c om posi tio n of th e c om ple x f or it s e le me nts a nd
e l ab o ra te s th e b o nd i ng o f l ig an ds wi th Fe (I I I ) a nd io ns C , H, O, N, F e ( I II ) a lon g wit h f unc ti ona l itie s of
g i v es th e id e a o f p r ob abl e ch el at e t yp e st r uc tu r e of th e c ar bi mi de , c ar bo nyl bon ds to m et al a re c onfi r m ed by
c o mp le x . T h e P L sp ec tr u m of Sc hi f f ba se an d c om ple x usi ng UV- Vis a nd P L e le ct r on tr a nsi tio ns a nd pe a ks in
d e t er min e d s e p a ra te l y ex pl a in t he q uen ch i ng of pe a k r es pe ct ive spe c tr a . The se e vid en ce a re sup por te d by
s i g na l o f S c h iff ba se af t er bo n di ng of Fe (I I I ) wit h F TI R si gna ls a s pe r spe c tr a l st udie s in wor ks of B . S inha
2
1
c ar b im id e b o n d s in t he co mp le x. I n Fi g ur es 2A a nd 2B et al., he nc e th es e a na lys es of S ch if f ba se a nd C OR M
t h e P L e mi s s io n pe ak s of Sc hi f f ba se an d C ORM c om ple x no t on ly pr ov e th e c om posi tio n but a ls o
c o mp le x re s p e c tiv el y sh ow t he qu en ch i ng of s ign al .
P L s p e c tra o f S ch if f b ase an d co mp le x su p por t f or
pr ob abl e st ru ct ur e a nd f unc ti ona li ties in th e c ompl ex .
t h e b o n d in g , s tr uc tu re an d n at ur e of co mp le x c on- 3.1 b FTIR spectrum of Schiff base and CORM
t a in in g S c h iff b as e an d CO l ig an d si mu l ta ne ous ly complex: F TI R spe c tr um of S ch if f ba s e a nd
l i n k e d wi th F e (III) i on s t o g iv e mo re st a bi l it y f or th e c om ple x we r e de te r mi ne d to e sti ma t e the
c h e la te . Ac c o rd in g t o PL sp ec tr a, t he PL i nt ens ity of f unc ti ona li tie s pr e se nt in side th e m ole c ule s a nd to
Sc h iff b a s e a t 8 1 5 nm . du e t o no n b ond ed a nd P i c onfi r m th e f or ma t ion of C ORM c om ple x on th e ba s is
e l ec tr o n s wa s q u e n ch ed by Fe (I I I) b ond i ng i n c om ple x of si gna ls r ep r ese nt ed by f unc ti ona l gr oups in
p ro v in g M L CT t ra ns it i on an d co or di n at e/ c ova le nt fi nge r pr int a nd f unc ti ona l r eg ion s of s pe ct r a.
l i n k a g e s o f c a rb imi d e bo n ds wi th a me ta l i on . Ove r al l F igu re 3A r ep r ese nt s th e F TI R spe c tr um of S c hif f
t h e se s p e c tra e la b or at e ch el at e na t ur e of com pl ex ba se , in th is spe c tr um pr e se nc e of c ar bi mi de bond –
c o n ta in i n g CO li g an d l ik ed wi th pl a ne r Sc hi f f ba se C =N- wa s e la bor a te d du e to si gna l a t 1918 a nd

J. Chem. Sci. (2 0 2 0 ) 13 2: 44
P age 5 of 12 44
Figure 2. ( A) P L em m i s s io n s pe ctr u m of s chi ff bas e . (B ) P L em m i s s i on s pec tr u m of com pl ex.
Table 1. M LC T t r ans i tio ns of no n bo nd ed /P i el e ct ron s of l ig ands and d el ect ro ns of F e(I II ).
Ab so r p t i o n o r e mi s s io n
p eak s h o w n i n UV-V is . O r
P L s p ec t ru m
S
c
h
i
f
f
b
a
s
e
t
r
a
n
s
i
t
i
o
n
Met al C OR M com pl ex cha rge t rans f er t rans i t io n
5
UV - Vi s . Ab s o rp t i o n at 35 5 n to P i ab s or pt ion m axi m a A 1 g t o T 2 g and A1 g t o A2 g fr om d s t at e of F e(I II ) fo r sp l i t t i ng
n m .
P L q u en c h i n g a t 8 1 5 n m .
fr om bon di ng of car b i m id e and C O s pec ies
P i t o P i rel ax ati on – que nch i ng due t o F e(I II) and car b i mi d e
l in kage
n to P i r ela xat io n-
no qu en ch in g

4
4
Pa g e 6 o f 1 2
J. Chem. Sci. (2 020) 1 32: 44
FTIR spectra of Schiff base
A
9
2.00
9
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
9.8
9.6
9.4
9.2
9
9
9
9
9
9
9
9
9
8
8
8
8
%T
8
8.90
4
000
3600
3200
2800
2400
2000
1800
1600
Frequency cm
1400
1200
1000
800
600
400
-1
FTIR spectra of CORM complex
B 5
0.0
4
4
4
8
6
4
%T
42
4
3
3
3
0
8
6
4
3
3.0
000
4
3600
3200
2800
2400
2000
1800
1600
1400
1200
1000
800
600
400
Frequency cm-
1
Figure 3. ( A ) F TI R s pe ctr u m of S ch if f bas e l ig and. (B ) F TIR s pec tr u m of C OR M com p l ex.
-
1
-1
1
9
7
1
c
m
.
T
h
e
s
i
g
n
a
l
s
a
t
5
3
1
,
6
6
5
a
n
d
8
0
5
c
m
c
a
r
b
i
m
i
d
e
m
e
t
a
l
b
o
n
d
.
O
v
e
r
a
l
l
a
l
l
t
h
e
s
e
o
b
s
e
r
v
a
t
i
o
n
s
re p re s e n t th e fi n g er pr i nt i de nt i ty of ar om at ic gr ou ps le a d to pr ov e th e c he la te na tu re of th e c om ple x a nd
fr o m b e n z a ld e h y d e an d ni t r oan i li ne . Si g nal s a t 255 5 oc ta he dr a l si te of S ch if f ba se wit h m et al io n a nd f r e e
-1
a n d 2 6 7 3 c m a re at t ri b ut ed t owa rd s t he a ro ma ti c c ar bo nyl gr ou ps ov er it . Ta ble 2 th ro ws ligh t on
n i t ro a n d n it ri le en t it y o f Sc hi f f ba se . Si g nal s f r om spe c ifi c si gna ls of th e F TI R spe c tr um f or the
-1
3 0 3 4 to 3 3 7 9 c m ar e r ai se d i n t he sp ec tr u m due to f unc ti ona li tie s in th e S ch if f ba se a nd th e c om ple x.
t h e p re s e n c e o f a rom at ic – OH an d ca rb i mi de h ydr ox yl
s i d e in t e ra c tio n s i n Sc hi f f ba se . I n Fi g ur e 3 B F TI R 3.1 c XRD
(X-ray
diffraction)
pattern
s p e c tru m p ro v e s f un ct io na li t i es pr es en t i n C ORM of complex: As pe r XR D pa tt er n of th e c ompl ex in
Fe ( III) c o mp le x e l ab or at es t he p res en ce o f ca r bim id e F igu re 4, th e c om ple x e vid en ce d to r hom bohe dr a
m e t a l b o n d a n d s i de CO l ig an ds ov er t he met al io n. c ry sta ll ine pa c kin g f or m et al io n a nd li ga nds , it
-
1
Si g n a ls a t 1 7 6 0 an d 18 2 2 cm
p re s e n c e CO g ro up s ov er Fe (I I I) me ta l i on in th e c om ple x. The di ff r a ct ion pa tt er n gi ve s si gna ls f or
el a bo ra t es th e e la bor a te s th e st ru ct ur e a nd m or phol ogy f or C OR M
-1
c o mp le x . T h e s ig n al s at 1 936 an d 19 6 9 cm
a re m et al io n pl an es in a n oc ta he dr a l e nvi ro nm e nt of
a t tr ib u te d to F e (II I) b ond ed wi th ca rb i mi de l in ka ge in S ch if f ba se a nd c ar bo nyl li ga nds, F e( I I I ) of the
t h e c o mp le x . T h e br o ade ni n g of si g na ls i n c om ple x c om ple x a re in oc ta he dr a l si te s of pa c king w ith
-1
FT I R s p e c tru m a t 25 8 5 an d 2 884 cm i s at t ri b ute d to li ga nds in c om ple x, he nc e ph ase pu ri ty of com ple x
c ar b im id e a n d CO l in ka ge s at Fe (I I I) i on an d cov al en t c ry sta l ha ve be e n pr ov ed by XR D pa tt er ns . The X RD
a ro ma t ic -O li n k a ge t o Fe (I I I) f ro m Sc hi f f b ase ne a r to da ta is de te r mi ne d usi ng m ill er in dic e s of pa tte r n,

J. Chem. Sci. (2 0 2 0 ) 13 2: 44
P
a
g
e
7
o
f
1
2
4
4
Table 2. M at c h in g of F TI R s ig na ls el ab or at in g th e fu nct io n al i ti es of S chi ff bas e and C OR M com pl ex.
S
i
g
n
a
l
i
n
F
T
I
R
s
p
e
c
t
r
u
m
S
c
h
i
f
f
b
a
s
e
f
u
n
c
t
i
o
n
a
l
i
t
y
C
O
R
M
c
o
m
p
l
e
x
f
u
n
c
t
i
o
n
a
l
i
t
y
-
-
-
1
1
1
1
1
3
1
2
9 6 9 c m
7 6 0 c m
0 3 4 c m
Ca r bi mi de bo nd -C =N -
A bs en ce of CO
A r om a tic - OH
P re s e nc e of an ar om at i c ni t ro gr oup
P re s e nc e of n it ri le ent i t y
C
a
r
b
i
m
i
d
e
l
i
n
k
e
d
t
o
F
e
(
I
I
I
)
P res en ce of l in ked C O l ig ands over Fe ( II I )
Et her aro m ati c- O - l in kage wi t h F e(I II )
Ou t of pl ane n i tr o gr oups
-
1
1
7 9 0 a n d 1 8 2 4 c m -
5 5 5 a n d 2 5 8 5 c m
P
r
e
s
e
n
c
e
o
f
l
i
n
k
e
d
n
i
t
r
i
l
e
e
n
t
i
t
y
S
c
h
e
r
e
r
’
s
f
o
r
m
u
l
a
a
n
d
p
a
c
k
i
n
g
o
f
p
l
a
n
e
s
a
n
d
i
t
w
a
s
3
.
1
d
T
E
M
image
and
SAED
pattern
m a t c h e d wi th o c ta he dr al Fe (I I I) d at a i n JC PDS c ar d of Complex: The TEM im a ge of th e c ompl ex in
n o . 8 5 -3 8 5 4 . As p er Ta bl e 3, t he cr ys t al pa ra me te r s of F igu re 5A th ro ws li ght on sph er i ca l e lo nga te d
rh o mb o h e d r a l p a c ki n g o f co mp le x cl e ar ly r epr ese nt ed m or phol ogy a nd som e a ggr e ga tio n of com ple x
t h e o c ta h e d ra l p a ck i ng of t he me ta l i on wi th li ga nds m ole c ule s due to sup r am ole c ula r ne ig hbour in g
p ro d u c in g rh o mb o he dr al cr ys t al . Hen ce , XRD da ta bo ndin g in te ra c ti ons. The pa r tic l e si ze s of com ple x
p ro v e d th e p h a s e pu r it y , cr ys t al pa ck i ng , ge om e tr y, c ry sta ls r an ge d f r om 60 nm to 75 nm . B ut m ost of the
c
h
e
l
a
t
e
o
c
t
a
h
e
d
r
a
l
n
a
t
u
r
e
o
f
C
O
R
M
c
o
m
p
l
e
x
.
p
a
r
t
i
c
l
e
s
o
f
c
o
m
p
l
e
x
m
o
l
e
c
u
l
e
s
e
x
h
i
b
i
t
e
d
a
v
e
r
a
g
e
s
i
z
e
XRD spectra of com plex
Fe(III) ion in carbim ide and CO ligand environm ent
O ctahedral rhom bohedral crystal sym m etry
1
1
2000
0000
[
020]
8
6
4
2
000
000
000
000
0
[121]
001]
[
[
Fe(III) in rhom bohedra]
[
111]
[
002]
2
0
40
60
80
2
Theta
Figure 4. XR D pat t ern of t he C om pl ex.
Table 3. C ry s t a l pa ra m e te rs of CO R M F e( I I I) co m pl ex m at ched wi t h s t an dar d F e(I II) oct ah edr al J C PD S car d .
Cr y st a l l i te p l an e s
0
(
(
Mi l le r In d i ce s )
h ,k ,l )
d Ca lcu la ted A
Lat t i ce C ons t a nt
a and b A fr om m ai n XR D p e ak
at t het a = 37. 5 of C OR M com p le x c ry st a l
fr om rh om bohe dr a
2
2
2
0
0
d = a / H( h ?k ?l )
or
d S t andar d A
JC P DS car d no. - 89- 385 4
F e(I II)
Rh o mb o h e dr a o f
o c ta h e d r a l c h el a te ph as e
2d S in h = n k
0
1
0
0
1
0 1
2 1
20
0 2
1 1
5. 08 8
4. 03 2
7.039
3. 08 9
6. 33 4
5. 089
4. 045
7.043
3. 083
6. 329
a s t andar d = 3. 249
b s t andar d = 5. 266
a cal cul at ed = 3. 251 and
b cal cul at ed = 5. 272

4
4
P
a
g
e
8
o
f
1
2
J. Chem. Sci. (2 020) 1 32: 44
Figure 5. ( A) TEM im a g e of com pl ex. (B ) S AED pat t ern of com pl ex.
ra n g e 6 0 n m wh i ch ca n p ass t hr ou gh ce l l me mb ra ne s c om ple x f or f ur the r wa te r -l ovi ng na tu r e a nd
b y s u p ra m o lec u l ar i nt er ac t io ns ea si l y. Th e TEM bi ome di c al a ppl ic at ion s.
re s u lt s we re ma t c he d wi th XRD d at a an d pr ov ed th e
c h e la te o c ta h e d ra l n at ur e o f co mp le x wit h th e
c ry s ta ll in e s ta t e fo r g ood wat e r so l ub il i ty an d f ur the r 3.2 Antimicrobial properties Schiff base
b i o co mp a t ib i l ity . Th e SAE D p at te rn s gr ea t ly m at ch ed and complex for better biocompatibility
wi t h XR D d a ta w it h cr ys t al li n e d ot p at te rn s a s pe r
A
s
p
e
r
t
h
e
i
m
a
g
e
s
o
f
b
a
c
t
e
r
i
a
l
c
u
l
t
u
r
e
s
a
n
d
z
o
n
e
s
o
f
Fi g u re 5B. Ov e ra l l TE M i mag e an d SAE D p at te r n of
in hibi tio n e xhi bit ed by S ch if f ba se a nd c om ple x on
t h e c o mp le x h a d pr o ved t he mo rp ho l og y of th e
Figure 6. (A ) t o ( C) A nti m i cr ob ia l ef f ect s of sc hi ff bas e l ig and at 25 ppm . on (A ) E-Coli.-Gram negative bacteria,
(
B
)
K
l
e
b
.
-
G
r
a
m
n
e
g
a
t
i
v
e
b
a
c
t
e
r
i
a
,
(
C
)
S
t
a
p
h
.
a
u
r
e
u
s
-
G
r
a
m
p
o
s
i
t
i
v
e
b
a
c
t
e
r
i
a
.

J. Chem. Sci. (2 0 2 0 ) 13 2: 44
P
a
g
e
9
o
f
1
2
4
4
Figure 7. (A ) t o ( C) A nti m ic ro bi al ef f ect s of C OR M com p le x at 25 pp m . on (A ) E-Coli.-Gram negative bacteria,
B) Kleb.- Gram negative bacteria, ( C) Staph. aureus- Gram positive bacteria.
(
g ra m-p o s i t iv e a n d g ram -n eg at i ve ba ct er i a in F ig- 3.3 Anticancer potential of Schiff base
u re s 6A t o 6 C a n d 7A t o 7 C, i t cl e ar ly i nd ic at ed th at and complex by in vitro MTT assay on MCF-7 cells
t h e S c h iff b a s e a nd co mp le x sh ow b et te r an t im ic r obi al
As pe r F igu re 8, pH st im ula te d hi ghe r a ntic a nc e r
a ct ivi ty ha d be e n sho wn by c om ple x th an S ch if f ba s e
c om pa re d wit h f r ee c ont ro l c el ls on th e b as is of
in vitro MT T a ssa y on MC F - 7 br e as t c an ce r c ell s. The
c el l vi ab ili tie s de te r mi ne d a re r el a te d to c ytoto xic ity
a nd a nti ca nc e r e ff e c ts on th es e c an ce r c el ls at 5, 10,
a ct i v iti e s. T h e COR M co mp le x sh ows hi g he r a ct ivi ty
t h a n S c h iff b a s e an d as pe r Ta bl e 4 , es pe ci a lly on
g ra m-p o s i t iv e b a c t er ia , hi g he r ac t iv i ty was es ti ma te d
t h a n g ra m-n e g a t iv e ba ct er i a. So t he COR M c om ple x
e x h ib it h ig h e r b io co mp at i bi l i t y t ha n Sc hi f f b as e, due
t o re le a s e o f CO , Sc hi f f ba se l ig an d an d Fe (I I I ) m et al
i o n in s i d e b a c te r ia l ce l ls ca us in g i nt er ac t io ns wit h
DNA. S o , th e c o mp le x sh ow hi g he r ce l l co mpa ti bil it y
a n d in t e rn a liz a t i on d ue t o i ts ch el at e su pr am o le cu la r
n a t ur e p ro v in g it s ap pl i ca bi l it y i n b io med i cal fie lds .
1
5
,
2
0
,
2
5
p
p
m
.
C
o
n
c
e
n
t
r
a
t
i
o
n
s
o
f
d
o
s
e
s
o
f
S
c
h
i
f
f
b
a
s
e
a nd C ORM c om ple x. Hig he r c el l li ne a popt os is w as
obs er ve d a t 25 ppm . Giv ing do se- de pe nd en t and pH
tr i gge r ed c yto toxi c ity of C ORM c om ple x. About 77%
Table 4. An t i - m i c ro bi a l ac tiv it ie s of S chi f f ba s e and com p le x com par ed fo r gr am -p os i t iv e and gr am -n ega ti ve ba ct e ri a .
Zon es of i nhi bi t io n fo r gr am -p os i t i ve bac ter ia / gr am -n ega ti ve bact e ri a a s
zo n e d i am et er i n m m . fo r con cent rat i ons of dr ug/ dos e of com p le x or Sc h if f
b
a
s
e
2
5
l
g
/
m
L
(
p
p
m
.
)
i
n
v
i
t
r
o
o
n
b
a
c
t
e
r
i
a
l
c
e
l
l
s
Ty p e/ n a me o f b a ct e ri al cu lt ur e in A ga r br o th
[
as p e r Fi g u re s 6 A t o 6 C an d 7 A t o 7 C]
F
o
r
S
c
h
i
f
f
b
a
s
e
F or C OR M com pl ex
E. Co l i (g r am -v e )
Kl eb .( g ra m -v e )
S ta p h a u re u s (g ra m ?ve )
10 m m .
5 m m .
8 m m .
35 m m .
15 m m .
48 m m .

4
4
Pa g e 1 0 o f 1 2
J. Chem. Sci. (2 020) 1 32: 44
7
6
5
4
3
2
1
0
action of CORM complex
action of Schiff base
io n a nd pH tr i gge r ed a ct ion on c an ce r c el l e ndoc yto sis
a nd a popt osi s a re th e m ai n e nti tie s whi ch pl ay r ole in
a nti ca nc e r e ff e c ts of th is ne w C ORM c om ple x . The s e
a ll obs er va t ions a re sup por te d a nd pr ov ed by D AP I
st ai nin g im a ge of MC F - 7 c el ls a ft e r th e a c tion of
C ORM c om ple x by MT T a ssa y. I n F igu re 9, it w as
obs er ve d th at th e c om ple x a ft e r e ndoc yt osi s s hr inks
c an ce r c el ls f as tly a ft e r in cu ba tio n a nd sho w D AP I
fl uor e sc en ce a t c en te r of c el ls und er a m ic ros c ope .
Thi s ob ser va t ion in dic a te s th e a ct ion of r el e as e d s pe -
c ie s wit h DNA pr od uci ng pH- se nsi tiv e R OS fl ux
in side c an ce r c el ls f r om C ORM c om ple x r es ul ting in
in tr ins ic a popt osi s of MC F - 7 c el ls.
0
0
0
0
0
0
0
5
10
15
20
25
Concentrations of dosing for complex and schiff base in ppm.
Figure 8. An t i c a n cer ac tiv it ie s of s ch if f ba s e an d C OR M
co mp l e x b y M TT as s ay on MC F- 7 ce l ls .
3.4 Mechanism for antimicrobial activity
and anticancer potentials of the CORM complex
As pe r S ch em e 2, whe n C ORM c om ple x e nte r s into
ba c te r ia l or c an ce r c el ls wit h pr od uct ion of R OS ( r e -
a ct ive ox yge n spe c ie s) li ke O , OH, OOH a nd H O
2
2
2
a ft e r e ndoc yt osi s a nd ly soso ma l di ge stio n a t a cid ic pH ,
it c au se s pr om ine nt bi oc om pa tib le e ff e c ts on the s e
c el ls. C ORM c om ple x r el e as e C O li ga nd, S ch if f ba s e
a nd di ssoc ia te F e( I I I ) in side a ci dic pH of c el ls , s o by
pH tr i gge r it r el e as es pr ot on fl ux, C O, in te r c at ions
in side c el l or ga ne ll es . The R OS pr od uce d in side ba c -
te r ia l c el ls by th es e spe c ie s on th e ba si s of c e ll
m ole c ule in te ra c ti on e nte r s in to r oug h or ga ne lle s a nd
m ito ch ondr i a of c el ls di stur bi ng m em br a ne po te ntia ls
of c el l or ga ne ll es a nd da m ag e DNA or m uta te d D NA .
The f r ee e le ct r ons f r om F e( I I I ) io ns, C O li ga nd , S c hif f
ba se a ct ivi ty, in te r c at ion a nd pr ot on fl ux a r e ke y
f ac t or s di stur bi ng th e c an ce r c el l m ito ch ondr ia a nd
m uta te d DNA. Ove r al l th es e in tr ins ic pa th wa ys of
a popt osi s by C ORM c om ple x c au se hi ghe r a ntic a nc e r
e ff e c ts th an S ch if f ba se on MC F - 7 c el ls wit h p r oba ble
R OS- li pid pe r oxi da tion m ec ha ni sm whi ch a re pH - re -
spo nsi ve a nd C O si gna lin g a ff e c tin g bi ome dic a l
Figure 9. DAP I s ta in ing im a ge of in te rn al iza t io n of
co mp l e x fo r a p op t o s is of MC F - 7 ce lls .
a p o p to s is wa s g iv e n by COR M co mp le x at 25 pp m
d o s e , h e n c e , th e c om pl ex sh ow g ood cy t ot ox ic it y on
c an c e r c e ll s a n d p ro ved i ts po t en ti a l ap pl i ca ti o n in th e
b i o m e d ic a l a re a . Su pr am ol ecu lar ch el at e na tu re to
p a s s fro m c e ll b a rr i er s, p res en ce ke y si g na li ng C O
l i g a n d a n d S c h iff ba se wi th el e ct ro n p ro vi di ng F e( I I I )
1
9
,
2
2
,
2
3
a
c
t
i
v
i
t
i
e
s
.
He nc e, th is ne w C ORM c ompl ex
pH trigger
CORM Complex(Excitation at 385 nm.)
emission at 815 nm.
+
3+
[
Release of H / Fe / CO and Schiff base at acidic pH in lysosome]
+
-
Fe(III) to Schiff base CT transition
VB + e to CB in Fe(III) - (free electrons)
Dissociation-mitochondrial disruption
.
. .
[CO] and Schiff base releasing
at lysosomes pH change --- ROS in cells- O
2
, OH , OOH
Mitochondrial cyt.-c destruction and caspase activation
Apoptosis of cancer cell
Scheme 2. Me cha ni s m f or ant i m ic robi al and ant i ca nce r act i vi t i es of com p le x.

J. Chem. Sci. (2 0 2 0 ) 13 2: 44
P
a
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1
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f
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2
4
4
c l ea rly in d i c a te s p o te nt i al bi o med i cal ap pl i ca ti ons f or
a n t i mic ro b i a l a n d an t ic an ce r ac t iv i ti es .
R ut hen i um -Ni t ros yl com p lex es wi t h equ at ori a l 1 H-
i nadaz ol e l ig ands Inorg. Chem. 57 107 02
. S hai kh A R , Gi ri dh ar R and Yad av M R 20 07 Bi s mu t h
nor fl oxa ci n com pl ex: S ynt he s i s , phy s i coc hem i c al a nd
ant i m ic ro bi al eva lu at i on Int. J. Pharm. 6 24
. Gu erra W, de An drade Aze vedo E, de S ouz a Mo nt e ir o
A R , B ucci are ll i -R o dr ig uez M, C hart on e- S o uz a E ,
Nas c im e nt o A M, F ont e s A P , Le Moy ec L a nd
P ere ir a -M aia E C 200 5 S y nt hes i s , cha ract eri za ti o n , a nd
ant i bac t eri al act i vi ty of t hree pal l adi um (I I) com p le x es
of t et ra cyc li nes J. Inorg. Biochem. 99 234 8
. Ej id ik e I and Aj i bade P 201 6 R ut hen i um (I II ) Co m-
pl exes of Het er ocyc l ic Tri d ent at e (O NN ) S ch i f f Ba se :
S ynt he s i s , C hara cte ri zat i on and i ts B io lo gi c al P ro pe r ti e s
as an An ti r adi cal and An ti p ro li fer a t iv e Age n t Int.
J. Mol. Sci. 17 60
6. Li M X, C he n C L, Zhan g D, Ni u J Y and J i B S 2 01 0
Mn( II) , C o(I I ) and Zn (I I) com p le xes wi t h het e r oc yc l i c
s ubs t i tu t ed t hi os em i carb azones : S ynt he s i s , cha ra c te r i -
zat i on, X- ray cry s t al s t ruct ur es and ant i t um o r c om p ar -
i s on Eur. J. Med. Chem. 45 316 9
. Manjunath M, Kulkarni A D, Bagihalli G B, Malladi S a nd
Pa ti l S A 20 17 Bio -imp or ta n t a ntip y rin e de riv e d S ch if f
Ba s e s a n d th ei r t ra n sit io n m e ta l c o m p le xe s : S y nt he si s,
spe ct rosc opi c char act er iz a ti o n, a nt i m ic rob ial , an th elm in tic
and DN A c leav a ge i nv est i g at i on J. Mol. Struct. 1127 31 4
. Hr anj ec M, S t arcev ic K, P avel i c S K, Lu ci n P , Pa v el i c
K and Zam o l a G K 201 1 S ynt he s i s , s pec tro sc o pi c
cha ract eri za ti on and ant i pr ol i fera ti ve eva lu at i on in vitro
of nov el S chi f f B a s es rel at ed t o ben zi m i dazo l es Eur.
J. Med. Chem. 46 227 4
. Hu ang H, C hen Q, Ku X, Men g L, Li n L, Wa ng X, Z hu
C , Wa ng Y, C hen Z, Li M, J i a ng H, C hen K, Di n g J a nd
Li u H 201 0 A S eri es of a-H et eroc ycl i c C arbo xa l de h yd e
Thi os em i carb az one s In hi bi t Top ois o m era s e II a Ca t -
al yt ic Act i vi ty J. Med. Chem. 53 304 8
0. B adea M, C al u L, C hi fi riu c M C , B le otu C , Ma r i n A,
Io n S , Io ni ¸t a G, S t ani ca N, Mar u ¸t es cu L, La za r V,
Mar in e s cu D and Ol ar R 201 4 Ther m al beh av i o ur o f
s om e nov el ant i m i crob ial s bas e d on com pl exes wi t h a
S chi ff B as e bea r i ng 1, 2, 4-t ri azo le pha rm ac oph or e J.
Therm. Anal. Calorim. 118 1 145
3
4
4
. Conclusions
Th e n e w c a rb o n yl - Sch if f ba se COR M co mpl ex of
Fe ( III) e x h ib ite d r ho mbo he dr al p ack i ng an d c he la te
n a t ur e wi th a n o c t ah ed ra l si t e o f l ig an ds . Th e com pl ex
h a d e x h ib ite d 6 0 n m me an p art i cl e di a met e r a nd
c ry s ta ll in e o v a l m or ph ol o gy as co nfi rm ed b y XR D
p a t t e rn a n d T EM an al y si s. Th i s ch el at e wit h C O
re l ea s i n g a b il it y h as t he p ot en ti a l t o pa ss ce l l ba r r ie r
wi t h s u p ra m o lecu la r na t ur e an d he nc e sh ow be tt er
b i o co mp a t ib i l ity th an Sc hi f f b ase . Th e q uen c hin g of
s i g na l in P L s p ec tr u m el a bo ra te d t he bo n din g of
Fe ( III) io n wi th Sc hi f f ba se an d CO l ig an d. Fur t he r-
m o r e , th e c o mp lex ex hi b it s ROS i n b act er ia l a nd
c an c e r c e ll s a fte r t he r el ea se of t he Sc hi f f b ase , F e( I I I )
a n d CO b y p H tri g ger . Th e COR M co mp le x sho ws
b e t t e r b io c o mp a t ib i li t y by in vitro t ha n Sc hi f f ba se .
Th e s y n e rg ic e ffe ct s o f t he r el ea se of CO, Sc h if f ba se
a n d in t e ra c tio n o f Fe (I I I) wi th mi t oc ho nd ri a i n side th e
c el l s a re th e k e y f act o rs f or ce l l b io co mp ati bi lity.
He n c e , th i s CO R M co mp le x of Fe (I I I) ex hi bi ts a n
i n t ri n s ic p a th w ay f or ap op t os is of ca nc er ce l ls . Ove r al l
t h i s CO RM c o mp le x h as po t en ti a l ap pl i ca ti on in
5
7
8
9
b i o m e d ic a l fi el ds
b i o co mp a t ib i l ity .
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Acknowledgements
1
1
Th e a u th o r i s t h an k f ul to an al yti ca l in s tr u m en tat i o n l abo-
r at o ry , J ay s i n g p u r Co ll ege , J ay s in gp u r , I nd ia f or pr ovi di ng
s o m e s p ec t ro s co p i c ch ar ac ter iz a ti on s of s am p le s , and t o t he
Bi ot e ch n o l o g y l ab o ra t or y of S m t. K . W . Co ll eg e, San g l i fo r
p r ov i d i n g c el l c u lt u r es an d in vitro te s tin g f aci lit ie s .
1. S i nha D, Ti war i A K, S i ngh S , S h ukl a G, Mi s h ra P,
C handr a H and Mi s hr a A K 200 8 S ynt hes i s , cha r a ct e r-
i zat io n and bi ol ogi cal act i vi t y of S chi f f B as e ana l og u es
of i ndol e- 3- carbo xa l dehy de Eur. J. Med. Chem. 43 1 60
Compliance with ethical standards
Conflict of interest Th e au th or s de cl are th at th ey hav e no 12. S onm e z M and S¸ eke rci M 201 0 A New Het er oc y c l i c
c
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fl
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c
t
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f
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n
t
e
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e
s
t
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S chi ff B a s es and It s Met al C om pl exe s Synth. React.
Inorg. Met.-Org. Chem. 5714 489
1
3. B arot K P , Man na K S and Gh a t e M D 201 3 De si g n ,
s ynt hes i s and ant i m ic ro bi al act i vi t i es of s om e n ov el
1, 3, 4-t hi adi azo le, 1, 2, 4-t ri azo le- 5-t hi one and 1, 3 -t h ia -
zol an -4- one der iv at i ves of ben zi m i dazo l e J. Saudi
Chem. Soc. 21 S 3 5
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