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  <xsd:element id="mbrx_StockIssuedDuringPeriodSharesIssuedForConsultingAgreement" name="StockIssuedDuringPeriodSharesIssuedForConsultingAgreement" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="mbrx_StockIssuedDuringPeriodSharesWarrantExercises" name="StockIssuedDuringPeriodSharesWarrantExercises" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="mbrx_StockIssuedDuringPeriodValueAdditionalCommitmentShares" name="StockIssuedDuringPeriodValueAdditionalCommitmentShares" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="mbrx_StockIssuedDuringPeriodValueIssuedForConsultingAgreement" name="StockIssuedDuringPeriodValueIssuedForConsultingAgreement" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="mbrx_StockIssuedDuringPeriodValueTerminationOfAgreement" name="StockIssuedDuringPeriodValueTerminationOfAgreement" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="mbrx_StockIssuedDuringPeriodValueWarrantExercises" name="StockIssuedDuringPeriodValueWarrantExercises" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="mbrx_StockholdersEquityAdjustmentsReverseStockSplit" name="StockholdersEquityAdjustmentsReverseStockSplit" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="mbrx_StockholdersEquityAdjustmentsReverseStockSplitShares" name="StockholdersEquityAdjustmentsReverseStockSplitShares" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_SubmissionOfNDAAndReceiptOfFirstMarketingApprovalForSaleOfALicensedProductMember" name="SubmissionOfNDAAndReceiptOfFirstMarketingApprovalForSaleOfALicensedProductMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_SubscriptionReceivableMember" name="SubscriptionReceivableMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_The2015StockPlanMember" name="The2015StockPlanMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_The2020AtmAgreementMember" name="The2020AtmAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_The2021ATMAgreementMember" name="The2021ATMAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_UnderwrittenPublicOfferingMember" name="UnderwrittenPublicOfferingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="mbrx_VendorPrepaymentsAndDeposits" name="VendorPrepaymentsAndDeposits" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="mbrx_WPDPharmaceuticalsMember" name="WPDPharmaceuticalsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_WarrantIssuedInApril2021ForConsultingMember" name="WarrantIssuedInApril2021ForConsultingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_WarrantIssuedInAugust2021ForConsultingMember" name="WarrantIssuedInAugust2021ForConsultingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_WarrantIssuedInSeptember2022ForConsultingMember" name="WarrantIssuedInSeptember2022ForConsultingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_WarrantLiabilityLongTermMember" name="WarrantLiabilityLongTermMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_WarrantLiabilityMember" name="WarrantLiabilityMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="mbrx_WarrantsDisclosureTextBlock" name="WarrantsDisclosureTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_WarrantsIssuedInApril2018ForConsultingMember" name="WarrantsIssuedInApril2018ForConsultingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_WarrantsIssuedInApril2019Member" name="WarrantsIssuedInApril2019Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_WarrantsIssuedInApril2020ForConsultingMember" name="WarrantsIssuedInApril2020ForConsultingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_WarrantsIssuedInAugust2019ForConsultingMember" name="WarrantsIssuedInAugust2019ForConsultingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_WarrantsIssuedInDecember2020ForConsultingMember" name="WarrantsIssuedInDecember2020ForConsultingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_WarrantsIssuedInFebruary2017Member" name="WarrantsIssuedInFebruary2017Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_WarrantsIssuedInFebruary2018Member" name="WarrantsIssuedInFebruary2018Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_WarrantsIssuedInFebruary2020Member" name="WarrantsIssuedInFebruary2020Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_WarrantsIssuedInJuly2017ForConsultingOneMember" name="WarrantsIssuedInJuly2017ForConsultingOneMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_WarrantsIssuedInJuly2017ForConsultingWithExercisePrice1800Member" name="WarrantsIssuedInJuly2017ForConsultingWithExercisePrice1800Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_WarrantsIssuedInJuly2017ForConsultingWithExercisePriceOf1446Member" name="WarrantsIssuedInJuly2017ForConsultingWithExercisePriceOf1446Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_WarrantsIssuedInJune2018AndExpiringDecember222023Member" name="WarrantsIssuedInJune2018AndExpiringDecember222023Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_WarrantsIssuedInJune2018AndExpiringJune212023Member" name="WarrantsIssuedInJune2018AndExpiringJune212023Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_WarrantsIssuedInJune2018Member" name="WarrantsIssuedInJune2018Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_WarrantsIssuedInMarch2019Member" name="WarrantsIssuedInMarch2019Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_statement-statement-note-2-basis-of-presentation-principles-of-consolidation-and-significant-accounting-policies-prepaid-expenses-and-other-current-assets-details" name="statement-statement-note-2-basis-of-presentation-principles-of-consolidation-and-significant-accounting-policies-prepaid-expenses-and-other-current-assets-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_statement-statement-note-2-basis-of-presentation-principles-of-consolidation-and-significant-accounting-policies-schedule-of-fair-value-measurements-recurring-and-nonrecurring-details" name="statement-statement-note-2-basis-of-presentation-principles-of-consolidation-and-significant-accounting-policies-schedule-of-fair-value-measurements-recurring-and-nonrecurring-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_statement-statement-note-2-basis-of-presentation-principles-of-consolidation-and-significant-accounting-policies-schedule-of-property-plant-and-equipment-useful-lives-details" name="statement-statement-note-2-basis-of-presentation-principles-of-consolidation-and-significant-accounting-policies-schedule-of-property-plant-and-equipment-useful-lives-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_statement-statement-note-2-basis-of-presentation-principles-of-consolidation-and-significant-accounting-policies-tables" name="statement-statement-note-2-basis-of-presentation-principles-of-consolidation-and-significant-accounting-policies-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_statement-statement-note-4-accrued-expenses-and-other-current-liabilities-accrued-expenses-and-other-current-liabilities-details" name="statement-statement-note-4-accrued-expenses-and-other-current-liabilities-accrued-expenses-and-other-current-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_statement-statement-note-4-accrued-expenses-and-other-current-liabilities-tables" name="statement-statement-note-4-accrued-expenses-and-other-current-liabilities-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_statement-statement-note-5-warrants-assumptions-used-details" name="statement-statement-note-5-warrants-assumptions-used-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_statement-statement-note-5-warrants-tables" name="statement-statement-note-5-warrants-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_statement-statement-note-5-warrants-warrant-activity-details" name="statement-statement-note-5-warrants-warrant-activity-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_statement-statement-note-5-warrants-warrants-outstanding-details" name="statement-statement-note-5-warrants-warrants-outstanding-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_statement-statement-note-6-equity-assumptions-used-details" name="statement-statement-note-6-equity-assumptions-used-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_statement-statement-note-6-equity-restricted-stock-unit-activity-details" name="statement-statement-note-6-equity-restricted-stock-unit-activity-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_statement-statement-note-6-equity-stock-based-compensation-details" name="statement-statement-note-6-equity-stock-based-compensation-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_statement-statement-note-6-equity-stock-option-activity-details" name="statement-statement-note-6-equity-stock-option-activity-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_statement-statement-note-6-equity-tables" name="statement-statement-note-6-equity-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_statement-statement-note-7-income-taxes-reconciliation-of-unrecognized-tax-benefits-excluding-amounts-pertaining-to-examined-tax-returns-details" name="statement-statement-note-7-income-taxes-reconciliation-of-unrecognized-tax-benefits-excluding-amounts-pertaining-to-examined-tax-returns-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_statement-statement-note-7-income-taxes-schedule-of-components-of-income-tax-expense-benefit-details" name="statement-statement-note-7-income-taxes-schedule-of-components-of-income-tax-expense-benefit-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_statement-statement-note-7-income-taxes-schedule-of-deferred-tax-assets-and-liabilities-details" name="statement-statement-note-7-income-taxes-schedule-of-deferred-tax-assets-and-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_statement-statement-note-7-income-taxes-schedule-of-effective-income-tax-rate-reconciliation-details" name="statement-statement-note-7-income-taxes-schedule-of-effective-income-tax-rate-reconciliation-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_statement-statement-note-7-income-taxes-summary-of-valuation-allowance-details" name="statement-statement-note-7-income-taxes-summary-of-valuation-allowance-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_statement-statement-note-7-income-taxes-tables" name="statement-statement-note-7-income-taxes-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_statement-statement-note-8-commitments-and-contingencies-future-minimum-liabilities-details" name="statement-statement-note-8-commitments-and-contingencies-future-minimum-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_statement-statement-note-8-commitments-and-contingencies-lease-cost-details" name="statement-statement-note-8-commitments-and-contingencies-lease-cost-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_statement-statement-note-8-commitments-and-contingencies-tables" name="statement-statement-note-8-commitments-and-contingencies-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="mbrx_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>
