Vibrational properties of heme-nitrosoalkane complexes in comparison with those of their HNO analogs, and reactivity studies towards nitric oxide and Lewis acids.

C-Nitroso compounds (RNO, R = alkyl and aryl) are byproducts of drug metabolism and bind to heme proteins, and their heme-RNO adducts are isoelectronic to ferrous nitroxyl (NO-/HNO) complexes. Importantly, heme-HNO compounds are key intermediates in the reduction of NO to N2O and nitrite to ammonium in the nitrogen cycle. Ferrous heme-RNO complexes act as stable analogs of these species, potentially allowing for the investigation of the vibrational and electronic properties of unstable heme-HNO intermediates. In this paper, a series of six-coordinate ferrous heme-RNO complexes (where R = iPr and Ph) were prepared using the TPP2- and 3,5-Me-BAFP2- co-ligands, and tetrahydrofuran, pyridine, and 1-methylimidazole as the axial ligands (bound trans to RNO). These complexes were characterized using different spectroscopic methods and X-ray crystallography. The complex [Fe(TPP)(THF)(iPrNO)] was further utilized for nuclear resonance vibrational spectroscopy (NRVS), allowing for the detailed assignment of the Fe-N(R)O vibrations of a heme-RNO complex for the first time. The vibrational properties of these species were then correlated with those of their HNO analogs, using DFT calculations. Our studies support previous findings that RNO ligands in ferrous heme complexes do not elicit a significant trans effect. In addition, the complexes are air-stable, and do not show any reactivity of their RNO ligands towards NO. So although ferrous heme-RNO complexes are suitable structural and electronic models for their HNO analogs, they are unsuitable to model the reactivity of heme-HNO complexes. We further investigated the reaction of our heme-RNO complexes with different Lewis acids. Here, [Fe(TPP)(THF)(iPrNO)] was found to be unreactive towards Lewis acids. In contrast, [Fe(3,5-Me-BAFP)(iPrNO)2] is reactive towards all of the Lewis acids investigated here, but in most cases the iron center is simply oxidized, resulting in the loss of the iPrNO ligand. In the case of the Lewis acid B2(pin)2, the reduced product [Fe(3,5-Me-BAFP)(iPrNH2)(iPrNO)] was identified by X-ray crystallography.

iTHRIVE 365: A Community-Led, Multicomponent Health Promotion Intervention for Black Same Gender Loving Men.

Although health inequities among Black same gender loving men (SGLM) are well documented (e.g., chronic psychological disorders, HIV, suicide), there are few accessible, culturally affirming, and community-led interventions designed to reduce these inequities. The present manuscript describes the process through which we developed iTHRIVE 365, a multicomponent health-promotion intervention designed by Black SGLM for Black SGLM. We utilized a community-based participatory research approach (CBPR) that included collaboration between THRIVE SS, a Black SGLM-run community-based organization, and a multisectoral team of public health, research, and digital design professionals to develop the intervention. A five-phase development process included four phases of focus groups and a technical pilot to assess community priorities and incorporate input on each feature of the intervention. Directed content analysis indicated that participants wanted a multicomponent and technology-mediated intervention that promotes health knowledge and motivation, Black SGLM social support, access to affirming healthcare, and housing and economic resources. iTHRIVE 365 combines multilevel and culturally affirming intervention features to combat the effects of oppression and ultimately promote Black SGLM's biopsychosocial health.