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  <xsd:element id="dffn_ConvertiblePreferredStockMakewholeProvisionMinimumSharePrice" name="ConvertiblePreferredStockMakewholeProvisionMinimumSharePrice" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration"/>
  <xsd:element id="dffn_ConvertiblePreferredStockMakewholeProvisionProceedsFromIssueOfCommonStock" name="ConvertiblePreferredStockMakewholeProvisionProceedsFromIssueOfCommonStock" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="dffn_ConvertiblePreferredStockVotesPerShare" name="ConvertiblePreferredStockVotesPerShare" nillable="true" substitutionGroup="xbrli:item" type="us-types:perUnitItemType" xbrli:periodType="instant"/>
  <xsd:element id="dffn_CumulativeEffectOfChangeInAccountingPrinciple" name="CumulativeEffectOfChangeInAccountingPrinciple" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="dffn_DebtConversionConvertedInstrumentRelatedAccruedInterest" name="DebtConversionConvertedInstrumentRelatedAccruedInterest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="dffn_DeferredTaxAssetsCapitalizedCostsAndOther" name="DeferredTaxAssetsCapitalizedCostsAndOther" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="dffn_DeferredTaxAssetsOrphanDrugCredits" name="DeferredTaxAssetsOrphanDrugCredits" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="dffn_DiffusionLLCMember" name="DiffusionLLCMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="dffn_DilutiveSecuritiesEffectOnBasicEarningsPerShareChangeInFairValueOfWarrantLiability" name="DilutiveSecuritiesEffectOnBasicEarningsPerShareChangeInFairValueOfWarrantLiability" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_DocumentAndEntityInformation" name="DocumentAndEntityInformation" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element id="dffn_EffectIncomeTaxRateReconciliationLitigationSettlementChargePercent" name="EffectIncomeTaxRateReconciliationLitigationSettlementChargePercent" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="dffn_EffectiveIncomeTaxRateReconciliationChangeInFairValueOfWarrantPercent" name="EffectiveIncomeTaxRateReconciliationChangeInFairValueOfWarrantPercent" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="dffn_EffectiveIncomeTaxRateReconciliationOrphanDrugCreditsPercent" name="EffectiveIncomeTaxRateReconciliationOrphanDrugCreditsPercent" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="dffn_EffectiveIncomeTaxRateReconciliationSeveranceCostsPercent" name="EffectiveIncomeTaxRateReconciliationSeveranceCostsPercent" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_ExecutiveOfficersMember" name="ExecutiveOfficersMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="dffn_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityReclassificationOfWarrantsToApic" name="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityReclassificationOfWarrantsToApic" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_FinancialAdviserMember" name="FinancialAdviserMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="dffn_FinancingTriggerFromIssuanceOfCommonStock" name="FinancingTriggerFromIssuanceOfCommonStock" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="dffn_FormerEquityHoldersOfDiffusionLLCMember" name="FormerEquityHoldersOfDiffusionLLCMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_GeneralFinancialAdvisoryServicesMember" name="GeneralFinancialAdvisoryServicesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_HCWainwrightAndCoLLCMember" name="HCWainwrightAndCoLLCMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_InProcessResearchAndDevelopmentCostsIprdMember" name="InProcessResearchAndDevelopmentCostsIprdMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_January2018OfferingMember" name="January2018OfferingMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_LaboratoryEquipmentMember" name="LaboratoryEquipmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="dffn_MakewholeProvisionConversionPricePercentage" name="MakewholeProvisionConversionPricePercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_NonEmployeeStockOptionsMember" name="NonEmployeeStockOptionsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_NoteToFinancialStatementDetailsTextual" name="NoteToFinancialStatementDetailsTextual" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_NotesToFinancialStatements" name="NotesToFinancialStatements" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_NotesToFinancialStatementsAbstract" name="NotesToFinancialStatementsAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element id="dffn_NumberOfCommonStockPerUnit" name="NumberOfCommonStockPerUnit" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="dffn_NumberOfConvertiblePreferredStockPerUnit" name="NumberOfConvertiblePreferredStockPerUnit" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="dffn_OfferingCostsInAccountsPayable" name="OfferingCostsInAccountsPayable" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="dffn_OfferingCostsPolicyPolicyTextBlock" name="OfferingCostsPolicyPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="dffn_PercentageOfCommonStockOutstandingOwned" name="PercentageOfCommonStockOutstandingOwned" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant"/>
  <xsd:element id="dffn_PercentageOfTotalSharesEligibleForPlanReserveOnAnAnnualBasis" name="PercentageOfTotalSharesEligibleForPlanReserveOnAnAnnualBasis" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_PlacementAgentMember" name="PlacementAgentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="dffn_PreferentialDividendsPayble" name="PreferentialDividendsPayble" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element id="dffn_PrepaidExpensesDepositsAndOtherAssets" name="PrepaidExpensesDepositsAndOtherAssets" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="dffn_PrepaidResearchAndDevelopmentExpense" name="PrepaidResearchAndDevelopmentExpense" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="dffn_ProceedsFromIssuanceOfConvertiblePreferredStockNetOfOfferingCosts" name="ProceedsFromIssuanceOfConvertiblePreferredStockNetOfOfferingCosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="dffn_ProceedsFromReverseMergerTransaction" name="ProceedsFromReverseMergerTransaction" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="dffn_QualifiedFinancingMinimumAmountOfGrossProceeds" name="QualifiedFinancingMinimumAmountOfGrossProceeds" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_RES440Member" name="RES440Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_RES529Member" name="RES529Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="dffn_ReclassificationOfTheFairMarketValueOfWarrants" name="ReclassificationOfTheFairMarketValueOfWarrants" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_RestorGenexMember" name="RestorGenexMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_RestorgenexCorporation2015EquityIncentivePlanMember" name="RestorgenexCorporation2015EquityIncentivePlanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_ReverseStockSplitMember" name="ReverseStockSplitMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="dffn_ScheduleOfWarrantsOutstandingToAcquireSharesOfCommonStockTableTextBlock" name="ScheduleOfWarrantsOutstandingToAcquireSharesOfCommonStockTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_SeriesAConvertiblePreferredStockMember" name="SeriesAConvertiblePreferredStockMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_SettlementAgreementMember" name="SettlementAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="dffn_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsAssumedInPeriodDueToAMerger" name="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsAssumedInPeriodDueToAMerger" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="dffn_SharebasedCompensationArrangementsBySharebasedPaymentAwardOptionsAssumedInPeriodDueToAMergerWeightedAverageExercisePrice" name="SharebasedCompensationArrangementsBySharebasedPaymentAwardOptionsAssumedInPeriodDueToAMergerWeightedAverageExercisePrice" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration"/>
  <xsd:element id="dffn_StockIssuedDuringPeriodSharesMakewholeAdjustment" name="StockIssuedDuringPeriodSharesMakewholeAdjustment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="dffn_StockIssuedDuringPeriodSharesTotal" name="StockIssuedDuringPeriodSharesTotal" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="dffn_StockReclassifiedUponConversionOfPreferredStock" name="StockReclassifiedUponConversionOfPreferredStock" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="dffn_StockReclassifiedUponConversionOfPreferredStockShares" name="StockReclassifiedUponConversionOfPreferredStockShares" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_SuccessFeeAgreementCostsMember" name="SuccessFeeAgreementCostsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="dffn_TemporaryEquityStockIssuedDuringPeriodNewIssues" name="TemporaryEquityStockIssuedDuringPeriodNewIssues" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_The2016ConvertibleNotesMember" name="The2016ConvertibleNotesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_UnderwriterWarrantsMember" name="UnderwriterWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_VestMonthlyMember" name="VestMonthlyMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_VestQuarterlyMember" name="VestQuarterlyMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="dffn_WarrantExpense" name="WarrantExpense" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="dffn_WarrantExpenseChangeInFairValueAndOtherFinancingExpenses" name="WarrantExpenseChangeInFairValueAndOtherFinancingExpenses" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_WarrantsIssuedInConnectionWithTheJanuary2018OfferingMember" name="WarrantsIssuedInConnectionWithTheJanuary2018OfferingMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-10-convertible-preferred-stock-and-stockholders-equity-tables" name="statement-statement-note-10-convertible-preferred-stock-and-stockholders-equity-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-10-convertible-preferred-stock-and-stockholders-equity-warrants-outstanding-to-acquire-shares-of-its-common-stock-details" name="statement-statement-note-10-convertible-preferred-stock-and-stockholders-equity-warrants-outstanding-to-acquire-shares-of-its-common-stock-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-11-stockbased-compensation-fair-value-assumptions-details" name="statement-statement-note-11-stockbased-compensation-fair-value-assumptions-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-11-stockbased-compensation-stock-option-activity-details" name="statement-statement-note-11-stockbased-compensation-stock-option-activity-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-11-stockbased-compensation-stockbased-compensation-expense-details" name="statement-statement-note-11-stockbased-compensation-stockbased-compensation-expense-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-11-stockbased-compensation-tables" name="statement-statement-note-11-stockbased-compensation-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-13-income-taxes-deferred-tax-assets-and-liabilities-details" name="statement-statement-note-13-income-taxes-deferred-tax-assets-and-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-13-income-taxes-operating-loss-carryforwards-details" name="statement-statement-note-13-income-taxes-operating-loss-carryforwards-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-13-income-taxes-reconciliation-of-income-tax-rate-details" name="statement-statement-note-13-income-taxes-reconciliation-of-income-tax-rate-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-13-income-taxes-tables" name="statement-statement-note-13-income-taxes-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-14-fair-value-measurements-blackscholes-model-and-assumptions-details" name="statement-statement-note-14-fair-value-measurements-blackscholes-model-and-assumptions-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-14-fair-value-measurements-fair-value-on-a-recurring-basis-details" name="statement-statement-note-14-fair-value-measurements-fair-value-on-a-recurring-basis-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-14-fair-value-measurements-reconciliation-of-common-stock-warrant-liability-details" name="statement-statement-note-14-fair-value-measurements-reconciliation-of-common-stock-warrant-liability-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-14-fair-value-measurements-tables" name="statement-statement-note-14-fair-value-measurements-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-3-basis-of-presentation-and-summary-of-significant-accounting-policies-basic-and-diluted-earnings-per-share-details" name="statement-statement-note-3-basis-of-presentation-and-summary-of-significant-accounting-policies-basic-and-diluted-earnings-per-share-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-3-basis-of-presentation-and-summary-of-significant-accounting-policies-outstanding-dilutive-securities-details" name="statement-statement-note-3-basis-of-presentation-and-summary-of-significant-accounting-policies-outstanding-dilutive-securities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-3-basis-of-presentation-and-summary-of-significant-accounting-policies-tables" name="statement-statement-note-3-basis-of-presentation-and-summary-of-significant-accounting-policies-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-4-acquisition-assets-acquired-and-liabilities-assumed-details" name="statement-statement-note-4-acquisition-assets-acquired-and-liabilities-assumed-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-4-acquisition-pro-forma-financial-information-details" name="statement-statement-note-4-acquisition-pro-forma-financial-information-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-4-acquisition-purchase-price-consideration-details" name="statement-statement-note-4-acquisition-purchase-price-consideration-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-4-acquisition-tables" name="statement-statement-note-4-acquisition-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-5-property-and-equipment-property-and-equipment-details" name="statement-statement-note-5-property-and-equipment-property-and-equipment-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-5-property-and-equipment-tables" name="statement-statement-note-5-property-and-equipment-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-7-accrued-expenses-and-other-current-liabilities-summary-of-accrued-expenses-details" name="statement-statement-note-7-accrued-expenses-and-other-current-liabilities-summary-of-accrued-expenses-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-7-accrued-expenses-and-other-current-liabilities-tables" name="statement-statement-note-7-accrued-expenses-and-other-current-liabilities-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-8-convertible-debt-outstanding-convertible-notes-details" name="statement-statement-note-8-convertible-debt-outstanding-convertible-notes-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-8-convertible-debt-tables" name="statement-statement-note-8-convertible-debt-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-9-commitments-and-contingencies-tables" name="statement-statement-note-9-commitments-and-contingencies-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-note-9-commitments-and-contingencies-total-future-operating-lease-obligations-details" name="statement-statement-note-9-commitments-and-contingencies-total-future-operating-lease-obligations-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="dffn_statement-statement-significant-accounting-policies-policies" name="statement-statement-significant-accounting-policies-policies" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
</xsd:schema>
