Banca de DEFESA: RENÊ GOMES DA SILVA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : RENÊ GOMES DA SILVA
DATE: 29/06/2022
TIME: 09:30
LOCAL: Departamento de Química - sala 8B
TITLE:

NEW NEDAPLATIN ANALOGS CONTAINING CYSTEAMINE AS A LIGAND: A STUDY ON ANTITUMOR ACTIVITY AND OXIDATIVE DAMAGE

KEY WORDS:

Cancer, antineoplastics, platinum complexes.

PAGES: 110
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Química Inorgânica
SPECIALTY: Química Bio-Inorgânica
SUMMARY:

The Pt2+ coordination compounds have an application in the therapy of several types
of cancer, however they having severe side effects. In order to reduce the side effects,
it was proposed the synthesis and characterization of three new Pt2+ complexes
containing cysteamine as a ligand, in addition to an electrochemical study of
commercial complexes such as cisplatin, nedaplatin, oxaliplatin and carboplatin, which
were synthesized to reduce costs. The platinum residues from the laboratory were
treated to form potassium hexachloroplatinate - K2[PtCl6], which was reduced under
mild conditions to form K2[PtCl4], obtaining excellent yields >90%. In the synthesis of
organic salts, equimolar proportions of acids, sodium hydroxide and nitrate and silver
were used to form insoluble silver salts. Platinum precursors were synthesized by
adding excess KI to K2[PtCl4] to form K2[PtI4] in situ and then treated with ammonium
hydroxide and DACH ligand to provide the species cis-[Pt(NH3)2I2].and [Pt(DACH)I2]
with yields of 89.95 and 95.58%. With the silver glycolate and oxalate salts and the
platinum precursors in hand, the synthesis of cisplatin, nedaplatin and oxaliplatin was
carried out to carry out the comparative electrochemical study. In the synthesis of the
new complexes, K2[PtCl4] was reacted with cysteamine to form an intermediate
K[Pt(cysteamine)Cl2] to which Clions were replaced by glycolate, oxalate and
glycinate ligands, providing the K[Pt(cysteamine)(glycolate)],
K[Pt(cysteamine)(oxalate)] and K[Pt(cysteamine)(glycinate)] complexes with good
yields for the first (87.00%) and the third (75.98%) in which the success of the synthesis
was observed through FTIR characterization, electronic absorption spectroscopy,
thermogravimetric analysis and 1H, 13C and HSQC NMR. The voltammetric study of
the commercial compounds showed an increasing order K2[PtCl4] ~ K2[PtCl6] ~
cisplatin < nedaplatin < oxaliplatin < carboplatin, indicating that bidentate ligands
containing oxygen may be more efficient in electrochemical stability. The compounds
K[Pt(cysteamine)(glycolate)] and K[Pt(cysteamine)(glycinate)] showed low cellular
viability (>20%) in the tested MCF-7 strain, indicating promising results comparable or
superior to cisplatin, which justifies the performance of new studies in different strains
and also carrying out the in vivo study.

BANKING MEMBERS:
Externo à Instituição - SEVERINO ALVES JÚNIOR
Interna - 455.823.784-72 - BEATE SAEGESSER SANTOS - UFPE
Interno - 1508305 - JOAO RUFINO DE FREITAS FILHO
Externa ao Programa - 1884911 - MARIA JOSE DE FILGUEIRAS GOMES
Presidente - 2510144 - MONICA FREIRE BELIAN
Interno - 1581222 - WAGNER EDUARDO DA SILVA